limited points of observation give such results what estimate will suffice to comprehend the number of the Ocean's victims in its vast expanse of storm-visited surface! That millions of birds are annually thus destroyed cannot be doubted, and it is in this. way I would account for the numerical fluctuations noticed in the beginning of this article.

The migrations of birds have been well likened to the waves of the ocean, each billow of this living sea being made up of different species, the individuals of each species coming from more or less contiguous ones. This latter statement is proven from the fact that the main body of a given species arrives at a locality in the spring, as it leaves it in the fall, almost simultaneously, a single day usually sufficing to see a neighborhood stocked with its full quota, the onset of the numerous clans having been

"It was a strange and pitiful sight. Some were so fresh and perfect, and their feathers so unruffled, that it seemed impossible that they had been drowned. There were multitudes of wrens, with narrow, gauzy wings spread out, so that the wind swept them up and down on the sand, like autumn leaves sere and brown. Tiny creepers, looking ghastly with only a head and wing unburied, and moving as if alive; kinglets with their bright crowns defaced huddled into a group, where I counted a robin with fair unruffled breast, a kingbird, a summer yellowbird, and one orange-crowned warbler. The greatest number of any one species was the yellow-winged sparrow, both young and old. The grass finch and the song sparrow were abundant, as was also the familiar little pair bird. Of the goniaphea I do not remember a single specimen. They leave before September, I think. There were cowbirds, and one or two blackbirds, and no orioles. Blue jays one or two, much worn and defaced, and the common phebe more numerous. Belted king-fishers I saw once or twice, and of the picidæ, the red-head and the golden-winged, a single specimen each, as well as two of the downy woodpeckers.

"There were none of the varieties of the hirundinidæ, and but one or two of the thrushes, except the robin, which was rather numerous. Evidently that bird comes earlier and stays later than any others of his family. A single catbird came under my notice.

"I have observed that all through the summer more or less birds are drowned and thrown up on the beach. How many it is impossible to say, as they are soon covered with sand or carried away by prowling wildcats, whose tracks I constantly saw there. It is unlikely that during the breeding season any bird ventures so far from home as to cross the lake, and as there are no bays, and a sandy beach skirts all the wooded shores, the birds are not lost in flying voluntarily over the water, but are blown out and exhausted by baffling winds, fall down, and perish.

"

....

'If one had time to follow the beach during the season a pretty fair knowledge of the birds that haunt the shores of Lake Michigan might be gained. My observation was necessarily limited to a small space, but a wider research would no doubt give many other varieties of birds that perish in the lake. This is a very large percentage of loss no doubt, and must be reckoned as only the part belonging to Lake Michigan,

since the same thing happens on all the great lakes to some extent. . . . . "-Chicago Tribune, Sept. 3, 1881.

heralded, perhaps one or two, possibly six or eight days, previously. So that a gale would have precisely the effect noticed; that is, it would strike the long migrating line at a certain point where the victims taken would consist largely of the individuals belonging to the same neighborhood, perhaps of but one species or of more, as the case might be. The earlier and later migrants of that neighborhood would alone escape, except the fortunate few that succeeded by favoring circumstances in releasing themselves from the grasp of the storm. Thus it happens that a species usually abundant in a locality may suddenly become rare and yet the species hold its own over its general range.

That the ocean is responsible for the lives of many birds has long been known, but the idea that its victims annually reach such figures as to affect the numerical relation of species over extensive ・ areas has not, I think, been hitherto advanced. That such is the fact seems to me certain and it is with the idea of directing the attention of observers to this class of facts, as well as with the hope of eliciting information already gathered but not yet made known, that these pages have been written.

ON THE OSSICLE OF THE

ANTIBRACHIUM AS

FOUND IN SOME OF THE NORTH
FALCONIDÆ.

AMERICAN

BY R. W. SHUFELDT, M.D., CAPT. MED. DEPT. U. S. ARMY.

It does not seem possible that a bone the size of one which I am now about to describe could have been entirely overlooked by ornithologists, yet after a careful perusal of such parts of the works of the most prominent writers, as refer to the skeletology of the upper extremity I fail to discover the barest mention as to the existence of any such an one.

* The departure of birds in the fall is less regular than their return in spring. At least this is true of many species, as for instance the whole Sparrow tribe and many of the Warblers that saunter along as fine weather and an abundant food supply may tempt. The Swallows are the best examples of the other class. Their deliberative gatherings in the fall and prompt departure as though at a preconcerted signal are familiar to all.

My attention was called to the fact several months ago, while engaged in preparing the skeleton of a fine specimen of Circus hudsonius which I had secured for that purpose. The bird in question had been allowed to macerate for a long time, as a disarticulated skeleton alone was desired, so that disintegration of the soft parts was very complete and the bones sank to the bottom of the vessel containing my Hawk. Upon collecting these together and assorting them I found a pair of ossicles that I could not exactly account for, nor conceive as to which part of the bird's skeleton they rightfully belonged; of course the vertebral column, sternum, ribs, and pelvis could, one and all, be immediately discarded; first in order, naturally came the carpus and tarsus both of which were carefully examined, an examination that at the time I am free to confess threw no further light upon the subject, for the extremities of the long bones seemed to possess nothing that approached the appearance of additional facets for articulation, and the two free ossicles of the carpus seemed to exhibit all their usual characteristics as irregularly formed bonelets, not differing materially from their homologues in other birds of powerful flight. From the bony remains of my disjointed Marsh Harrier, I turned to the authors and authorities but only after thorough search through the works of those then at my command did I find that my labors were to terminate as already cited. Nothing was revealed or described that assisted me in the elucidation of such an unsuspected problem. My fowling piece and another specimen was the only and best resort left, but, as we all know, when a certain species of the class Aves becomes particularly desirable and must be had at once, no matter how common it may be, that bird suddenly develops a remarkable shyness, to say nothing of rarity, and such was the case here, for fully a month elapsed before a duplicate was taken; but it came at last in the shape of a fine adult female of the species already considered, and she was eagerly carried to my study.

My first suspicions were the first to be satisfied, and to this end I made an incision, carried only through the skin, around the shoulder, then carefully removed the integuments, allowing the quills of the primaries to remain, from the entire wing. This being successfully accomplished, the following condition of affairs at the wrist joint at once were disclosed to me, and carefully noted.

The usual long bones and carpal segments interested in the formation of the wrist joint of this Hawk held their positions and relations to each other as we find them described by ornithotomists generally; but superadded to these I found the ossicle which proved to be the counterpart of one of the pair I already had in my possession, found in the first specimen; in form it resembles an irregular parallelopiped or rather, and more correctly speaking, the frustum of a four-sided pyramid, its distal face being concave and its summit more or less tuberous. Its altitude measures 6 centimetres, while its base has a diameter of 3 centimeters, and is smooth, being covered with a thin layer of cartilage for articulation with a diminutive facet found on scapholunar and an extension of the usual horizontally compressed, distal end of radius that was produced anconad for that special purpose. The articu

lation is a true arthrodia, the little bone being perfectly free to glide over the surface in question, being restricted in its movements mainly by the ligaments that are attached to it and by the tendon of the extensor plicæ alaris that is found to be inserted at its summit. The principal ligaments are found to be those that are attached about its base to hold it in the position it occupies, and are blended with the carpal ligaments, generally; and an additional broad ligamentous expansion that is thrown out from the radial angle and aspect, from its summit to its base, to be inserted into the head of the metacarpus.

My sketch of the carpus in Circus, accompanying this paper, represents the bones of a life size from a large female of the species, entirely divested of all the engaged tendons and liga

ments, with the one exception already referred to, the limb being in a position of extreme extension. When the member is brought to the side in a position of rest, the ossicle no longer being held in its erect position by the stretched tendon of the extensor plica alaris, falls forwards and inwards to cover the ulnar aspect of the carpal articulation and forms in so doing an unusually rotund joint, particularly noticeable in the bird before the removal of the elastic integuments that tend further to hold it in this position in the closed wing.

As this little bone can in no way be considered as belonging to the bones of the carpus proper, I have named it the os prominens, and regard it in the same light and place it in the same category with the os humero-scapulare of the shoulder joint of others of the class, they being simple segments super-added to the series of vertebræ, modified or otherwise, of the avian skeleton, to fulfil a certain purpose.

The function of the os prominens can be studied, and its action thoroughly appreciated, by an examination of the wing in any of the Hawks where it is found; a very recently killed specimen being the best subject.

With the wing closed, it simply falls into the position that I have already endeavored to describe, and in doing so, it acts more as an additional protection to the anterior aspect of the carpal articulation than anything else - by no means an unimportant object among the Falconida; in the extended limb, where it becomes erect, and the elastic tendon of the extensor plica alaris is put on the stretch, we will at once observe that the surface of the integumental membrane, that is found in the triangular space between shoulder and carpus, is very much greater than if that tendon were simply inserted at the wrist-joint; this circumstance giving to these Raptorial birds a more extensive alar superficies, a very important auxilliary during their sustained flight aloft when, sailing in circles, they scan the earth below for their food.

The various bones in the cut are lettered to correspond with the same bones of my former published monographs, and the os prominens is here lettered os. p., and will be invariably so designated in future plates and papers when it becomes necessary to refer to it. I have thus far failed to discover this osteological character in any of the class except the Falconida, and doubt