ers are killed, stranger drones are readily received; thus the deterioration of the race is prevented.

A BLACK VARIETY OF THE COMMON RED SQUIRREL, Sciurus Hudsonicus Pallas. I have lately obtained a black specimen of the common Red Squirrel. It was killed at Letang, New Brunswick, where neither the Grey, nor the common Black Squirrel are known to occur.-G. A. BOARDMAN.

GEOLOGY.

DISCOVERY OF A HUMAN JAW IN A BELGIAN BONE CAVE.-Dr. Dupont has discovered in the Bone Caves of Farfooz, near Dinant, in Belgium, a strange human jaw. It is the opinion of Sir. W. V. Guise, and Rev. W. S. Symonds, who have examined this locality,

"That the geological period of the entombment of the human jaw, with the remains of the extinct animals with which it was associated, may be assigned to the epoch known to geologists as the low level drift period of Prestwich, a period recent in a geological sense, but enormously remote when measured by time, for the cold of the glacial epoch was not altogether passed, and the extinct mammalia were still in existence. It was the period of the deposition of the old river drifts of Menchecourt, near Abbeville, which contain their human flint implements, interbedded with the bones of the Mammoth and Rhinoceros; the period of the deposition of the ancient river beds near Salisbury, and other parts of England, which teach the same history; and also, they believe of the English bone caverns."— The Reader, London, Sept. 1, 1866.

A LIZARD-LIKE SERPENT FROM THE CHALK FORMATION OF ENGLAND. -Fossils indicating a creature of this character have been discovered by Mr. H. E. Seeley.-The Reader, London, Oct. 6, 1866.

DISCOVERY OF GENUINE CHALK IN COLORADO AND DACOTA.-" Chalk has at last been found in this country-genuine chalk, with flints and an abundance of fossils. Smoky Hill, Colorado, is an outlying mass of chalk, probably the only remainder of a vast mass which denudation has removed."—T. A. Conrad, Smithsonian Report, 1865.

Dr. F. V. Hayden has also discovered in Yankton, Dacota Territory, large deposits of a "nearly white, soft chalk," which "will be found to represent the White Chalk Beds of Europe, and be employed for similar economical purposes."-Amer. Journal Science and Arts, Jan. 1867.

CORRESPONDENCE.

ON THE PLUMAGE OF THE BLACK GUILLEMOT.-How does it happen that we find the Black Guillemot (Uria grylle Lath.), in full black plumage all winter? All our works on Natural History tell us they change to white or grey in winter, but I often get specimens which are black in mid-winter. May it not be that only the young are light in winter? I can hardly think it possible some would remain black, and others change; I can see no difference between my dark winter and summer specimens.-G. A. BOARDMAN, Milltown, Me.

NATURAL HISTORY CALENDAR.

ORNITHOLOGICAL CALENDAR FOR MARCH.-In this Calendar we have endeavored to indicate the average time of the arrival and departure of the migratory birds in the State of Massachusetts for this month; in years when the cold of winter ceases earlier or later than the average opening of spring, as well as in districts north or south of this State, the dates will be found to be respectively too early or too late, the difference increasing in the latter case with the increase of the difference in latitude. Thus, some birds wintering in the Southern States, reach Washington, D. C., in their northward migration three weeks earlier than they do Massachusetts; in Southern Pennsylvania two weeks, and Southern New York nearly one week earlier; while the same species commonly reach the middle of Maine some ten to twelve days later than they do Massachusetts.

1st to 10th.-Blue Birds, Song Sparrows, Robins, Purple Grakles, Red-winged Black Birds,Rusty Grakles and Cow Birds,begin to arrive. 10th to 20th.-The preceding become more common. Meadow Larks, Bridge Pewees or Phoebes, Snow Birds and Purple Finches, begin to arrive; the Hawks that in winter are represented by but few individuals, as the Marsh, Red-tailed, Red-shouldered, etc., increase in numbers by arrivals from the South. The Goshawks, Snowy Owls and other Northern visitors of the raptorial tribes mostly retire northwards.

20th to 31st.-All those previously arrived receive new accessions to their numbers, and become generally distributed. Grass Finches, Mourning or Carolina Turtle Doves, Passenger Pigeons (of late, uncertain visitors), and the Fox-colored Sparrows arrive; the Black Duck (Anas obscura), Canada and Brant Geese, Goosanders or Sheldrakes, Whistle-wings or Golden-eyes, Wood and Pintail Ducks, Red-breasted and Hooded Mergansers, Divers, and several species of Grebes begin to frequent the rivers and open ponds, as well as the coast. Some of the sea-fowl that are winter visitors, as the Eider Duck, Doublecrested Cormorant, Skuas or Jager Gulls, Black-backed and Laughing Gulls, and Guillemots, return northwards; other kinds, as the Redheaded, Canvas-back, Ruddy, Surf Ducks, Scoters, King, Eiders, Kittiwake and Bonaparte's Gulls, Arctic Tern, and other species of the Duck and Gull tribes begin to arrive from the South; Snow Buntings and such rare land birds as the Pine Grosbeak, White-winged Crossbill, the Arctic Three-toed Woodpecker (Picoides arcticus) and Lesser Redpoll, leave for the north, as do also many of the Butcher Birds. Such early breeding species as some of the Hawks and Owls pair during this month; some, as the White-headed Eagle, Duck Hawk

and Great Horned Owl, which begin their courtships as early as February, choose their eyries, and the former commences incubation. Blue Birds frequently pair before the end of the month, and taking possession of breeding boxes or holes in trees, guard them carefully against intruders.-J. A. A.

The Robins often lay the eggs for their first brood in March, in the vicinity of Salem.-EDs.

PROCEEDINGS OF SCIENTIFIC SOCIETIES.

AMERICAN ACADEMY OF ARTS AND SCIENCES, Boston. Jan. 8, 1867. The following papers were read:

Thermogenesis, or Theory of Temperature, by Dr. J. D. Whelpey, of

Boston.

The Object and Method of Mineralogy, by T. Sterry Hunt, of Montreal, Canada.

On the Inequalities produced in the Moon's Motion by the Secular Variation in the position of the Ecliptic, by G. W. Hill, of Cambridge.

ESSEX INSTITUTE, Salem. Jan. 7, 1867.-The following paper was presented:

A Catalogue of the Birds of North America contained in the Museum of the Essex Institute, with which is incorporated a List of the Birds of New England, with brief critical notes, by Elliott Coues, M. D., U. S. A.

Mr. C. Cooke made some remarks on the Sea Coco (Lodoicea sechellarum); and Mr. E. Bicknell exhibited sections, mounted for the microscope, of the poison fangs of the Rattlesnake.

ACADEMY OF SCIENCES, Chicago. Annual Meeting, Jan. 8, 1867.—Dr. William Stimpson was appointed Director of the Museum, to fill the vacancy caused by the death of Major R. Kennicott.

The President, Geo. C. Walker, Esq., delivered his annual address. The Secretary then submitted his annual report.

The following resolutions were passed:

WHEREAS, The appropriation for the Illinois General Survey has been too small to allow of a sufficiently rapid examination:

Resolved, That this Academy desires to express its sense of the great importance of this work, and its hope that the appropriation will be increased to a degree that will carry on the State Survey with a greater rapidity than heretofore.

Resolved, That our Representatives in the General Assembly be respectfully requested to favor the increase of the appropriation.

BOSTON SOCIETY OF NATURAL HISTORY. January 2, 1867.-Mr. Horace Mann exhibited a large panoramic photograph of the crater on the summit of Haleakala, the mountain of East Maui, Hawaiian Is

lands. This crater is situated on the summit of Haleakala, its rim being at the average elevation of 10,000 feet above the sea. Its depth is about 2,000 feet, and the comparatively level plain which forms its floor, therefore, at an elevation of 8,000 feet. The whole circumference of the crater is thirty or thirty-five miles, it being one of the largest in the world.

Mr. Winwood Reade, of England, who was present as a visitor, read to the Society a paper upon the habits of the Gorilla, the result of his personal investigation in the Gaboon region.

Section of Entomology, Jan. 23.-Mr. Scudder remarked on a small collection of fossil insects obtained by Prof. William Denton, in the Tertiary, probably Miocene, beds of Green River, near the boundary line of Colorado and Utah Territories. The number of species amounts to about fifty, though they are so imperfectly preserved as to be difficult, if not impossible, to identify.

The most abundant forms are Diptera, and they comprise indeed two-thirds of the whole number, either in the larval or imago state; the others are mostly very minute Coleoptera, and there are besides several Homoptera, minute parasitic Hymenoptera, Pteromali, a Myrmica, a moth, and a larva, apparently allied to that of Limacodes.

The perfect Diptera are mostly small species of Mycetophilidæ and Tipulida. There are besides some which are apparently Muscidæ. Among the larvæ are those of Muscidæ, together with other larvæ belonging to species of which the adults are not represented on these stones. The Homoptera belong to genera allied to Issus, Gypona, Delphax and some of the Tettigonidæ. The collection does not agree, in the aggregation of species, with any of the insect beds of Europe, or with the insects of the amber fauna on the shores of the Baltic.

A paper was also read On Monstrosities observed in the wings of Lepidopterous Insects, and on the method of producing them artificially, by L. Trouvelot.

ILLINOIS NATURAL HISTORY SOCIETY Bloomington, Annual Meeting, December 19, 1866. The following resolution was passed:

Resolved, That the corresponding secretary and the general commissioner be instructed to correspond and confer with the principals and professors of natural science of the various schools and colleges in the state, with naturalists and friends of natural science, with a view to the organization of local auxiliary societies, to the securing of local collections and the organization of a general system of exchanges, under the supervision of the Board of Directors.

Papers were presented to the society both at the June and the present meeting, by Prof. Marcy, of the Northwestern University, Dr. Vasey, Prof. Sewall, of the State Normal University, and Dr. F. Brendel, of Peoria.-Prairie Farmer.

NOTE.-The Editors desire brief minutes, such as those given above, of every meeting of all the Scientific Societies in North Americi. A copy of the NATURALIST will be sent to each Secretary, personally, free of expense, so long as such reports are promptly sent in to this office.

THE

AMERICAN NATURALIST.

Vol. 1.—APRIL, 1867.-No. 2.

THE MOSS-ANIMALS, OR FRESH WATER

POLYZOA.

PLATE 3.

BY ALPHEUS HYATT.

Among all the creatures found in our pools and lakes, none are more pleasing to the eye when carefully examined, than the Moss-Animals. These delicate animalflowers may be found in communities, expanding their shadowy plumes in the darker recesses of our ponds, attached to the under side of submerged sticks, logs and

stones.

Figures 1, 2, and 3, in the plate, show three of these communities. In figures 2 and 3 the plumes are expanded, but in figure 1 they are withdrawn, as they always are when the colony is disturbed.

The moss-animals of our fresh waters are, with two exceptions, all members of one group, called Phylactolæmata, or animals with guarded throats; that is, having a little flap outside of the mouth, which guards this aperture. The two exceptions mentioned have not this characteristic, and, therefore, belong to the same division

Entered according to Act of Congress, in the year 1867, by the ESSEX INSTITUTE, in the Clerk's Office of the District Court of the District of Massachusetts.