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perhaps, the same mechanical basis as Helm
SPECIAL ARTICLES. holtz's explanation, it seems not amiss to ap
THIE FISHES OF PANAMA. proach it in this way. An attempt is being
In the Zoological Club of Indiana Unimade at a mathematical treatment.
versity in 1885 or 1886 President D. S. Jordan C. C. TROWBRIDGE, gave a résumé of the facts known at that time Secretary. concerning the relation of the marine faunas
on the two sides of Panama. It was jokingly DISCUSSION AND CORRESPONDENCE. remarked at that time that at the rate of HIGHER AND LOWER.
progress the canal might be finished by 1900
and that zoologists would have to bestir themTO THE EDITOR OF SCIENCE: In the American
selves to record the faunas as they exist before Naturalist for June, on page 413, L. J. C.
the Panama canal would mix things up. It takes exception to the custom of referring to
is now 1905 and the canal is not finished. In animals as ‘higher' and 'lower,' on the ground
the meantime the marine faunas have been that these terms tend to give the student an
dealt with by idea that the vertebrate affinities lie in a direct
1. GREGORY, L. chain, rather than forming a complicated,
W.: •Contributions to the
Palæontology and Physical Geology of the West branching system.
Indies,' Quart. Journ. Geol. Soc., Vol. 4, 1895, This criticism will strike some as a little
pp. 255-312. captious since the terms do not imply a direct
2. Fasox, WALTER: The Stalk-eyed Crustacea,' connection, but merely that some animals are Mem. Mus. Comp. Zool., Harvard College, Vol. on a higher plane than others, just as the XVIII., 1895, pp. 1-292. dwellers on the fifth floor of an apartment 3. GILBERT, C. H., and STARKS, Edwin C.: “ The house are higher than those on the fourth Fishes of Panama Bay,' Mem. Cal. Acad. Sci., Vol. floor. The terms generalized and specialized IV., pp. 1-226. fail to convey the idea intended because a Gilbert and Stark's conclusions are that: highly specialized animal may be low in the “The ichthyological evidence is overwhelmscale of life. The sloth is more specialized ingly in favor of the existence of a former than the monkey, but it would naturally be open communication between the two oceans, termed a lower animal; thus though what we which must have been closed at a period sufcall the ‘higher’animals are, as a rule, more ficiently remote from the present to have perspecialized than the 'lower' forms, they are by mitted the specific differentiation of a very no means invariably so. To revert to the large majority of the forms involved.” They apartment house it may be said that a family found that of the 82 families of fishes repreon the fifth floor might be related to one on sented at Panama all but 3 (Cerdalidæ, Cirthe fourth and another on the sixth and yet, hitidæ and Nematestiidae) occur also on the as a whole, the fifth floor people would be Atlantic side of Central America; while of higher than those below.
the 218 genera of our Panama list, no fewer
F. A. L. than 170, are common to both oceans.' FiftyA DENIAL.
four out of a total of 374, or 144 per cent., of TO THE EDITOR OF SCIENCE: In a circular the Pacific coast species are identical with sent out by The Macmillan Company ad- Atlantic coast species. vertising one of their recent publications, the I have just finished a consideration of the assertion is gratuitously made that I ‘uphold geographical distribution of the freshwater Wallace's position. Kindly allow me the fishes of tropical America and Patagonia as space to deny the statement and to explain applied to the Archihelenis-Archiplata theory that it arose first from a misapprehension, of von Ihering. The details will appear in which was later compounded by a clerical one of the volumes of the Hatcher reports of error—not mine.
Princeton University. The evidence there Hubert LYMAN CLARK. collected indicates that the Pacific slope fauna of tropical America has been derived from the Atlantic slope fauna. Only three of the genera of fresh-water fishes of the Pacific slope are peculiar to it; all the rest are identical with Atlantic slope genera. Even many species are identical on the two sides. The indications are that in the main the Pacific slope fauna was derived from the Atlantic slope fauna in times much more recent than the
be ample to keep apart two marine faunas is not necessarily a barrier to the intermingling of two fresh-water faunas. It is quite within the range of possibilities that the Atlantic slope fauna ascended the Chagres and succeeded in crossing the low divide and descended the Pacific rivers. The Chagres route has a rival farther south. In Colombia the Cordilleras form four separate chains. The east
... Bayano. Pimelodella modestus (Günther)......
. Esmeraldas. Pimelodella chagresi (Steind.) ...... Pimelodella gracilis (Val.).. Ancistrus chagresi (Eigenmann & Eigenmann) Hemiancistrus aspidolepis Günther.............. Bayano. ('hætostomus fischeri Steind.
. Bayano. Loricaria variegata Steind. .................... Bayano. Loricaria uracantha Kner & Steindachner..... . Bayano: Loricaria lima Kner.....
. Bayano. Sturisoma panamensis Eigenm. & Eigenm...... .. Bayano. Hoplias malabaricus Bloch....
Bayano. Hoplias microlepis Günther..
Western Ecuador. Curimatus magdalence Steind...
... Mamoni. Brycon striatulus (Kner) .....
Pacific slope of Panama. Astyanar panamensis Günther.
Bayano. Luciocharax insculptus Steind....
..Bayano. Eigenmannia humboldti (Steind)..
obliteration of the interoceanic connection between the Pacific and Atlantic. An examination of the distribution of the genera with representatives on the Pacific slope on the Atlantic side of the continent shows that nearly all have a very wide range and are found either in the Rio Magdalena or the Chagres. This indicates that the present fresh-water fauna of the Pacific slope crossed the divide somewhere near Panama. It is to be borne in mind that a barrier which may
ern, east of the Rio Magdalena, the central, between the Magdalena and its tributary, the Cauca, the western, west of the Cauca, and finally, a coast range. Between the western Cordillera and the coast Cordillera is a trough whose highest point is but 300 feet above sea level.
In the west Cordilleras to the east of this trough arise two rivers, both of which flow into the longitudinal valley, where one, the Atrato, flows to the north into the Caribbean,
the other, the San Juan to the south, and then through a break in the coast Cordilleras to the west to the Pacific Ocean. The height of land separating the two systems scarcely reaches a height of 100 m. This waterway is one of the strategic points in the geographical distribution of South American fishes and it is more than to be regretted that there is not a single record of a fresh-water fish from either of these rivers !
We are a little more fortunate about our knowledge of the fishes of the two sides of Panama, but are far from an exhaustive knowledge on the subject.
It would certainly be a disgrace not to make an exhaustive study of the fresh-water faunas of the two slopes before there is a chance of the artificial mingling of the two faunas. It ought to be urged upon congress to make provision for the biological survey of the canal zone if the president or the bureau of fisheries does not already possess authority to provide for it. The work should be under taken at once.
For the biological survey of the Atrato-San Juan route we must depend upon private enterprise, and it is to be hoped that the means for so interesting and profitable work will not be lacking when the volunteers for the work are so numerous and willing.
On the preceding page I give the fishes recorded from the Chagres on the Atlantic and the Bayano and its tributary, the Mamoni, on the Pacific side of Panama, together with the distribution on the Atlantic or Pacific slope of species found in one of the rivers, but not in the other.
C. H. EIGENMANN.
this species with four nursing young, at Washington, D. C., June 18, 1902.
The Milwaukee specimens were all taken in the daytime clinging to the trunks of shade trees between the sidewalks and curbs in thickly populated residential parts of the city.
On July 14 a female with a single rather large young clinging to her was brought to me at the Public Museum. A few days later a female with three much smaller and less developed young was brought in after having been kept in captivity for a day or two until the mother had died. The young of this group were approximately the size of those figured by Mr. Lyon in the above-cited paper.
On July 23 a female with four larger young was brought to the museum. In this case the mother and young were alive. They had been confined for some hours in a pasteboard box and were quite restless. The half-grown young were clinging indiscriminately to each other and to the mother, who seemed fairly mobbed by her numerous progeny. A few days later I was shown another female with but a single young.
Of this bat Mr. Lyon cites observations of two having two young each, two having three and the instance under his own observation of one having four. Adding my own observations to this, we have the following records for number of cases and number of young: 2 X 1, 2 X 2, 3 X 3 and 2 X 4.
On the face of this tabulation it would appear that three is the more common number of young and that a single young is as frequent as four. However, it is not improbable that the females with single young may have lost others of their families either by death or by their accidentally becoming detached.
Two embryos were found in each of two females included in the above table and three embryos were found in two other included instances; consequently, it is certain that either two or three young may be born, but it does not appear equally certain that as sma small a number as one may occur at a birth, although that number appears to be common to genera other than Lasiurus and, as Mr. Lyon states, probably Dasypterus.
THE NUMBER OF YOUNG OF THE RED BAT.
During the summer of 1904 four females of Lasiurus borealis with their young came under my observation, the data from which add to the information contained in a recent article on the subject by M. W. Lyon, Jr., in Proc. U. S. National Museum, Vol. 26, pp. 425-426, recording the capture of a female of
1 Presented before the Wisconsin Natural His tory Society, March, 1905.
It is interesting to note, as pointed out by Mr. Lyon, that this unusually large number of young is coincident with the possession of four mammæ, whereas two is the number known in other bats.
That the mammæ of an animal should be as many as the normal number of young produced would appear to be a reasonable proposition, but that the normal number of young equals the number of mammæ is quite a different one, from which many exceptions will suggest themselves. For instance, the seals have four mammæ, yet one young is the rule and two the exception among the species with which I am familiar.
The fact of an increased number of mammæ in these bats correlates well with the observed fact of an unusual number of young, and I would be pleased to know of farther observations that may tend to establish what is the average number.
HENRY L. WARD. PUBLIC MUSEUM, MILWAUKEE.
has certainly succeeded in making a most lucid statement in regard to every point. Where necessary he does not hesitate to indicate our lack of knowledge in regard to any structure, as when he discusses the nucleolus, and says that its substance is not well understood. Yet he does not refrain from stating his belief where it may be an aid to a clearer general understanding of the subject, as in the discussion of the pyrenoid, which he conjectures will prove to be a metabolic center of the chromatophore which is more or less prominent according to conditions of nutrition, whose most conspicuous activity is the formation of starch by the direct transformation of portions of its substance.'
In the discussion of direct-cell division the author suggests the possibility that this may be a reversion to early ancestral conditions, mitosis being regarded as phylogenetically a later process. With regard to centrospheres the author recognizes their existence in thallophytes only. As to the theory of the permanence of the chromosome Dr. Davis says ' it can hardly be said that the doctrine is established.'
In passing we note that the author regards the plasmodium of the slime molds as a coenocyte, and further that coenocytes of all kinds are to be regarded as multinucleate cells, and therefore units, instead of compound structures whose cells have not become separated by walls.
In the last article (IV.), devoted to cell unions and nuclear fusions, the author draws a sharp line of distinction between those which are sexual and those which are asexual. Under the latter (asexual) he includes the fusions of amoeboid cells to form plasmodia, the nuclear fusions in the teleutospores of smuts and rusts, and the nuclear fusions connected with
double fertilization. The remaining articles of this instructive publication will be looked for with keen interest.
PLANT CELL STUDIES. CNDER the title of 'Studies on the Plant Cell’ Dr. B. M. Davis is bringing together in a series of articles published in the American Naturalist (May, 1904, to April, 1905) what is known of the structure and activities of the plant cell. This is necessary because of the inadequacy and incompleteness of the accounts to be found in even the most recent botanical text-books. The author hopes, also, to help to change an attitude toward investigations on the plant cell that is unfortunately too prevalent among botanists,' i. e., to regard cytology as a very special field with an elaborate technique beyond the capabilities of the average botanist. In carrying out this plan the author divides the subject into six sections, riz.: (I.) The structure of the plant cell; (II.) the activities of the plant cell; (III.) highly specialized plant cells and their peculiarities; (IV.) cell unions and nuclear fusions in plants; (V.) cell activities at critical periods of ontogeny in plants; (VI.) comparative morphology and physiology of the plant cell. The treatment under each of these heads, as far as published, is very satisfactory, and the author
LEAF INTUMESCENCES. In the Sixteenth Annual Report of the Missouri Botanical Garden Dr. Hermann von Schrenk contributes an article on the interesting problem of the cause of intumescences paper describes 112 species, about three fourths of which are described here for the first time. More than two thirds of all the species enumerated are annuals.
which sometimes occur on the leaves of various plants. After a historical discussion of leafintumescences as observed by other investigators, the author describes the experiments which he made by spraying cauliflowers with various chemical substances. He found that by using ammonium copper carbonate he could produce intumescences at will, varying from minute papillae to large wart-like excrescences, dependent upon the size of the drops of the spray. Sections of these artificially produced intumescences showed that the mesophyll cells had become enormously enlarged, first lifting up, and later rupturing the epidermis. The giant cells were very thin-walled, and occurred in hair-like rows in which the outer cells soon died and became filled with air, while in those lying deeper 'very much reduced chlorophyll grains could be found.'
By means of careful experiments the author concludes that the peculiar growth of these cells is due to chemical stimulation of a kind hitherto unrecorded. Attention is directed to the fact that somewhat similar intumescences containing giant cells are formed as a result of insect punctures, which it is surmised are due to ‘some chemical influences exerted by the parent insect, the egg, or the larva. It is to be hoped that the experiments which the author has now in progress may throw additional light upon this interesting subject, especially the connection between these chemically produced giant cells and those produced in insect galls.
THE SMUT-FUNGI OF NORTH AMERICA. UNDER the title of North American Ustilagineae' Dr. G. P. Clinton publishes in the Proceedings of the Boston Society of Natural History (Vol. 31, No. 9) a paper of two hundred pages on the systematic botany of the smut-fungi of North America. The paper is the result of ten years of work (the last two years in the cryptogamic laboratory of Harvard University), during which the author has engaged in: (1) economic studies of the species found in Illinois, published in bulletins 47 and 57 of the Illinois Agricultural Experiment Station; (2) systematic studies, of which the present paper is the outcome; (3) the distribution of exsiccati, one century of which appeared in January, 1903; (4) spore germination studies, now under way.
In the present paper the specific descriptions are based upon the author's examination of the available material, which includes practically all of the European and American exsiccati. This insures a broader treatment than the order has hitherto received at the hands of fungologists. It is significant of the conservative tendencies of the author that although he describes 205 species and varieties, he finds it necessary to make but nine new species. Nor does he find it necessary to erect any new genera, so that his new names' are but three.
The order includes two families, USTILAGINACEAE, represented by Ustilago (72 species), Sphacelotheca (16), Melanopsichium (1), Cintractia (14), Schizonella (1), Mycosyrinx (1), Sorosporium (9), Thecaphora (9), Tolyposporella (8), Tolyposporium (2), and Testicularia (1); and TILLETIACEAE, represented by Tilletia (19 species), Neovossia (1), Tubercinia (2), Urocystis (12), Entyloma (127), Burrillia (3), Doassansia (11), and Tracya (1).
An admirable specific systematic list of host plants; a table showing the distribution of our species in other countries; a list of the more
THE CALIFORNIA POPPIES. Dr. E. L. GREENE, of the United States National Museum, publishes a revision of the California poppies (species of Eschscholtzia) in the June number of Pittonia. The paper is a continuation of work begun more than twenty years ago, and continued from that time to the present. The result is somewhat startling, even in this day of many species of hawthorns and violets. We may well repeat the author's remark, “that the species are so numerous, one might well regret,' which he follows with this his own defense: ‘but na. ture has yielded them, doubtless even more of them than are here enumerated. All told the