have seen; and there is this peculiarity in addition, that the under tail coverts remain pure white." This specimen had been previously described by Peale (Zoöl. U. S. Expl. Exped., 1848, p. 299) under the name of Procellaria gularis, but Dr. Coues, after expressing his doubts as to its probable relationship, provisionally referred it to E. mollis,* and there the matter has rested, the type, up to the present time remaining unique. The above description proved so nearly satisfactory that upon first reading it I felt little doubt as to the relationship of the bird in hand: but all uncertainty on this point has since been removed, for through the kind offices of Mr. Ridgway, the Smithsonian specimen "No. 15,706" is now before me. A comparison of the two at once establishes their perfect specific identity. The differences that obtain are just those which would be expected when the relative ages of the specimens are considered. Peale's example is a young bird, apparently in its first year; while mine, if not an adult, is certainly much older and probably in nearly mature plumage. Generally speaking, it may be said to differ from the type in having the predominating areas above pure cinereous instead of plumbeous; the crown and forehead much mixed with white; the lores and a conspicuous superciliary stripe pure white, unmingled with darker color; the transocular faciæ, though equally dark, much more restricted; and the white areas below,† considerably more extended and of a purer character. Of the stages in Æ. mollis, Dr. Coues says: "the older the bird the clearer and purer is the cinereous and the more trenchantly defined are the boundaries of the several differently colored areas; the difference in this respect being especially notable in the forehead and sides of the breast. Young birds are all over of a pretty uniform deep brownish ash or fuliginous cinereous; inclining to smoky brown on the wings and tail." And now a word as to the relationship which these interesting specimens bear to Æ. mollis. Of the latter I have only a single specimen, an adult, kindly furnished by my friend Mr. Allen, from the collection of the Cambridge Museum of Comparative Zoology. But the testimony which it affords, taken in connection * Upon looking more closely into the earlier history of the case I find that this arrangement was first instituted by Cassin, who, in the second edition of the U. S. Expl. Ex., places Peale's specimen under Procellaria mollis. The type of gularis has a pure white throat and light breast. with the excellent description of mollis given by Dr. Coues, is quite sufficient. The peculiar marking of the primaries in gularis, now confirmed by this second specimen, would alone be conclusive, but in addition, I find certain structural differences which were apparently overlooked by Dr. Coues. The tail of gularis is shorter and much less decidedly rounded than is that of mollis. This difference is best shown by the graduation of the rectrices. For mollis Dr. Coues gives the graduation as 1.30 (the specimen before me measures 1.05, but the bird is in a moulting state and the tail not fully developed), while in the two specimens of gularis, it is respectively only .60 and .90. Furthermore, gularis has the central pair of rectrices broader and more evenly rounded at the tips than are those of mollis. These characters, although of undoubted specific value, will by no means warrant generic separation, the general shape and proportions of the two birds being strikingly similar, and the bill and feet in this family the most important of all the generic characters — absolutely identical. Accordingly, while I follow Dr. Coues in referring Peale's bird to the genus Estrelata, I do not hesitate to reinstate it as a perfectly valid species. In view of the fact that both the previous descriptions are founded on a young bird, and that one of them (Peale's) is too superficial to be available in nice determinations, while the other, by Dr. Coues, is only incidental in character, I take the present opportunity to redescribe the species as follows: Estrelata gularis, (Peale), Brewster. PEALE'S PETREL. Ch. sp. similis mollis sed tectricibus caudæ inferioribus candidis; alis subtus fere ex toto candidis; duabus tertiis partibus pogonii interni abrupte albis; cauda breviori ac minus conspicue curvata; rectricibus mediis latioribus. Adult (?) plumage. No. 5224, author's collection, Mt. Morris, Livingston Co., New York, April, 1880. Upper parts, including the tail coverts and exposed surface of rectrices, pure cinereous, which deepens to plumbeous only on the occiput, rump and wings, the latter having the middle and greater coverts of the same tint as the back. The feathers of the back (but not those of the rump or occiput), with the greater and middle wing-coverts, broadly tipped with ashy-white, giving these parts a scaled appearance. The throat, jugulum, upper part of breast, and under tailcoverts, pure, silky white. The cinereous of the upper parts comes down along the sides of the neck, encroaching more and more and deepening in tint as it extends backward, until it throws across the abdomen a broad band of nearly pure plumbeous. Around this colored tract there is nowhere a definite line of demarcation: the cinereous of the neck fades imperceptibly into the white of the throat, and the edges of the abdominal bar become mingled with white, until the dark color is entirely lost along the sides under the wings, and at the beginning of the under tail coverts; while forward, on the lower part of the breast, and over the ventral region generally, the feathers are spotted, barred, or finely vermiculated, in varying shades of color. The sides of the head backward to behind the eye (where the band of color already described begins), are essentially white, but the feathers immediately below the eye are obscurely banded, and there is a narrow but distinct transocular fascia of a dark color, which barely interrupts a broad and pure white superciliary-line passing from the bill to a short distance behind the eye. The forehead and crown are much mixed with white. On the forehead the white forms a broad edging to the feathers and extending more narrowly around their tips confines the plumbeous ashy to triangular central patches; but towards the crown it becomes restricted to the edges alone and when the occiput is reached, gives way entirely to the uniform plumbeous of that part. The peculiar color and marking of the wings, alike in both specimens, has already been so well treated by Dr. Coues that I will save repeating these details by referring the reader to his description, previously quoted in the present article. But in this connection it is necessary to call attention to two points which are not there noticed. The first is, that the secondaries, as well as the primaries, have the white areas on their inner webs. The second, that each successive primary, beginning with the first, is lighter and more plumbeous than the preceding one; but with the first secondary, the color abruptly darkens again, becoming on the exposed portion nearly black, and continuing uniformly so to the tertials, which are of an equally dark cast. The bill is black; the tarsus, obscure flesh-color with a bluish tinge. The basal third of toes, with contained webs, pale yellowish; the terminal portion, black. Dimensions. Bill (chord of culmen), 1.03 inches. Height at base, .46; width, .42. Tarsus, 1.37. Outer toe and claw, 1.65; middle, 1.70; inner, 1.43. Wing, 9.88. Tail, 3.95; the graduation of the rectrices, .90. Young (3) No. 15,706, National Museum. Antartic Ocean, lat. 68° S., long. 95° W., March 21. (Peale's type of Procellaria gularis). Above cinereous-brown, inclining to black on the tips of the secondaries and tertials; below, sooty-plumbeous; throat and under tail-coverts white, transocular faciæ broad and dark. Otherwise generally similar to the adult (as represented by specimen No. 5224). Dimensions. Bill (chord of culmen), 1.05. Height at base, 50; width .45. Tarsus, 1.35. Outer toe and claw, 1.65; middle do., 1.65; inner do., 1.36. Wing, 9.80. Tail, 3.90; graduation of the rectrices, .60. But before leaving the subject it becomes necessary to consider a Petrel which was unknown when Dr. Coues investigated the * family. This is Estrelata defilippiana, described by Drs. Giglioli and Salvadori from four specimens taken off the coast of Peru in lat. 18° 4' S., long. 79° 35′ W. In comparing their supposed species with E. gularis "as described by Coues" the joint author's remark; "But our species differs.... in its smaller dimensions and slighter make (E.gularis being in size and make similar to E. mollis), in the cinereous coloration of its upper, and the pure white of its lower parts, while E. gularis would be dark-colored above and below having only the tail-coverts white." E. defilippiana also bill relatively, and in some specimens, absolutely longer." has a But these color-differences lose much of their significance when it is remembered that the bird "described by Coues" was the young of gularis. My more mature specimen agrees very closely with their description save that it is not "subtus omnino pure alba" (this is afterwards slightly qualified by "lateribus pectoris vix cinereo-tinctis"),— and it is by no means improbable that the fully adult gularis will be found to have the under parts wholly white.† The discrepancy in size is less easily reconciled. The birds examined by Drs. Giglioli and Salvadori are all apparently smaller than either of the known examples of gularis. But still the largest of the former approaches suspiciously close to the smaller of the two latter:- E. defilippiana, wing, 9.45; E. gularis, Æ. do., 9.80:- and furthermore, in respect to individual size, the Petrels are notoriously variable. Nor can a comparison of measurements taken by different persons always be relied upon. Different methods give widely divergent results.† Scarcely two *" On some new Procellariidæ collected during a voyage around the world in 1865-68 by H. I. M.'s S. 'Magenta.' By Henry Hillyer Giglioli, Sc. D., C. M. Z. S., Naturalist to the expedition, and Thomas Salvadori, M. D., C. M. Z. S., Assistant in the Royal Zoological Museum of Turin," Ibis 1869 pp. 63–65. Rowley also gives a superb figure of the bird in his Ornithological Miscellany (Vol. I; p. 255, pl. xxxiii) but adds nothing new to an account taken from the text of the Ibis article. + In speaking of the young of Æ. mollis Dr. Coues says: "The whole under parts are not notably different from the back, though, however, the dark color only occupies the tips of the feathers; their basal moiety remaining white." This statement is significant in this connection, for upon examining my specimen, I find that the plumbeous color below, and also on certain parts of the head and neck, is mainly confined to the tips of the feathers, their concealed portions being snowy-white. Since writing the above I find a curiously apropos illustration of this. In Peale's original description of the type specimen the "wing from the carpal joint" is given as 'ten and a half inches" while my measurement of the same bird made it 9.80, a difference of nearly three quarters of an inch. ornithologists of my acquaintance measure either the tail or the tarsus from precisely the same relative points. We are not told that Æ. defilippiana was actually compared with Æ. mollis and if extraneous data were alone made use of there is surely room for a doubt in this connection. Again in respect to the bills there is nothing to show whether the chord or the arc was measured. If the latter (they simply say "rostr. a fronte") the apparent discrepancy would be pretty satisfactorily explained. In summing up the matter, it is perhaps enough to say that Estrelata gularis finds its nearest known affine in E. defilippiana. To go further than this would be hazardous under the present conditions of the case, but the relationship of the two birds is so extremely close that larger suites of specimens may confidently be expected to bridge over the slight differences which now separate them. In such an event defilippiana, Giglioli and Salvadori, 1869, will of course give place to gularis, Peale, 1848. In concluding, I quote in full all that Peale has handed down to us relating to the life history of the species which he had the honor to discover and describe. It is, so far as I know, the only account that has ever been written. "This bird was found amidst icebergs, buffeting the storms and fogs of the Antartic regions. We saw but few of them, and obtained but a single specimen, on the 21st of March, while the Ship Peacock was enveloped in a fog, latitude 68° S., longitude 95° W. of Greenwich. Their flight was easy and not very rapid. They were silent, and alighted on the water to examine some slips of paper and chips purposely thrown from the boat." * SOME OBSERVATIONS ON THE MIGRATION BY W. E. D. SCOTT. WHILE showing some friends the astronomical observatory and accessories connected with the College of New Jersey at Princeton, on the night of October 19, 1880, after looking at a number of objects through the nine-and-one-half inch equatorial, we were * U. S. Expl. Exp., Zoölogy, p. 410. (Edition of 1858). |