fringes permanently attached to their branchial arches, which are not known to be replaced by, or to coexist with, internal gills. They are their sole organs of respiration, for their lungs are too imperfect and rudimentary to have much physiological importance. In frogs, toads, and salamanders, the external gills are replaced by internal ones, and these in turn by lungs.

Thus it will be seen that no Batrachian is permanently provided with internal gillsanity

1

Fig. 96.

Selachians and Batrachians agree in this, that their embryos have in their first stages external fringes growing from the outer surface of the gill arches, and these fringes have the same structure in both. The Selachians still further agree with frogs, toads, and salamanders, in the fact that the outer fringes are absorbed, and are replaced by internal gills. They differ from them, however, in the following particular. Selachians retain their internal gills permanently through life, while, de if such exist at all in the Batrachians jäst mentioned, it is only during the larval stage, and they are soon replaced by lungs. Selachians may therefore be said to pass through stages analogous to the first and second stages of Anourous Batrachians and salamanders. The other changes which the fissures pass through before the skate acquires its permanent form are as follows. The seventh fissure is closed up at a very early period. about the time that the dorsals are beginning to be formed. While the first arch bends and is drawn forward as already described in connection with the formation of the jaws, it at the same time becomes broader, so as to widen the distance between the mouth and the first fissure, or the second, after the first is partially closed.

SP

20

Newly-hatched Skate: a, yelk-sack in the cavity of the abdomen, connecting with the intestine, b; c, embryonic portion of the tail which disappears in the adult, and Corresponds with the portion of the tail behind the dorsal fins in the figures representing still younger stages; d, upper lip; e, developed facial disk.

The transformatio the spiracle,

The inner part of the first closes up, while the outer remains open (fig. 90, a), is somewhat enlarged, and retains its relative position to the eye. It is very soon widely separated from the other fissures by the rapid growth of the intervening parts, and still further by the extension of the pectoral fins forward between this remnant of the first fissure and those behind it, the former being thus thrown to the upper, and the latter to the under surface. The unclosed portion of the first branchial fissure is thus converted into thus described is of very great eat interest when compared with the changes which occur in the corresponding fissures of the air-breathing vertebrates, and enables us to establish an unexpected; homology, Reichert, in his most important investigations of the development of the gill arches (visceral Bogen of the pig, has shown that in this animal the first fissure is gradually separated from the others by the widening of the second arch, and for a time, even after all the others are closed up, forms a direct opening from the side of the neck into the pharynx. Afterwards it is divided into an outer and inner portion by a membranous septum; the former being the external auditory canst and the latter the Eustachian tube and the cavity of the tympanum. İt wüh hus be seen that the spiracle is not only a true branchial fissure in the first place, but that in the end it is

the one 97 HORSCH e bocus with the Eustachian tube

and outer auditory passage other by

are separated from each the membrane of the tympanumido of spiwji b. 97970) Professor Huxley, in a series of lectures on the Vertebrate Skeleton, in

.

discus

which the homologies and development t of it are great ability, sets forth a somewhat different view with regard to the formation of the external ear, and maintains that the first step is similar to that in the case of the eyes and nose, viz. : an "involution" ora “pushing ju" of the integument. Professor Huxley's observations were made on the chick, and he arrives at the same conclusions as Remak, leaving us to infer that the auditory passage and Eustachian tube have no connection with the branchial fissures. We have gone over the same ground in the} pig, and have found Reichert's observations, as mentioned above, fully confirmed. gitur further!

The relation of the spiracle to the branchial fissures is still shown by the fact that in some species, as in Scyllium and Læmargus, It,? like the others, is provided with respiratory fringes. In the skate this is not the case, but in n the adult a comb-like fold, old, resembling, and prob ably having the functions of, a gill, is found just within the spiracular opening."

zation]) #Oreq? bozniw For a description of the development of the mouth and nostrils, and some other details which have been omitted in these extended quotations, the reader is referred to Professor Wyman's Memoir. 913 bar ya1199fo ɔ ni stadenutak od obano “

big NOTES ON SOME OF THE RARER BIRDS OF 11 antic Rolling I VÀ MASSACHUSETTS. enfuilt to Por

920 t bus omezit Jamii off to jevo).

VISS DIE #TO↑ and lerob9q of 79JTEL 917 bus,19qqu chị BY J, A. ALLEN), gored 1 me? 911, bain d ei stuen indoned 12 (Continued from page 585.

BAIRD'S SPARROW Centronyx Bairdii Baird. Mr. C. J. Maynard while collecting Long-spurs and Snow Buntings on the Ipswich sand-hills, December 4th, 1868, had the good fortune to shoot the first specimen of this species thus far obtained east of the Missouri, so far as known. No other at least is yet on record, and but one other specimen seems to be extant. This is one of Audubon's types collected near the mouth of the Yellowstone, in the summer of 1843, and now in the Museum of the Smithsonian Institution.Mr. Audubon is the only naturalist who has previously 'met with' it. He He reports it as common at the locality where he discovered it, where he obtained both males and females and its nest. But very little is known respecting its migrations or its distribution. Its discovery in Massachusetts was quite unlooked for, Mr. Maynard thinks he saw others, but sup posing it to be some other species he made no especial efforts to obtain them. In his notes kindly communicated' to me he remarks: "I saw other specimens, and am confident that I detected it the preceding season, 1867. It is probable. that it is a regular winter visitor from the north, accom-! panying the C. Lapponicus and P. nivalis, for it does not seem probable that it should occur regularly so far from its. usunb habitat the distance being some over sixteen hundred miles and not be found in the intermediate space." and not be further observes, his specimen somewhat resembles the Baywinged Sparrow (Poocates gramineus), with which inexperienced ornithologists might easily confound it." It is

--Mr. Maynard gives a good figure of this specimen in his book on Taxidermy ("Guide to Naturalists in Collecting and Preserving Objects of Natural History") now publishing.

† Birds of America, Vol. vii, p. 359, pl. 500.

certainly nearer this than the Savannah Sparrow, Sparrow, with which it has been compared. "My specimen," he says, "also differs in size [from Audubon's*]. I give measurements of both for comparison, remarking that mine was measured from the fresh bird, while the other was from the skin.""

It differed in color as well as in size from the specimen described by Prof. Baird. The former difference is doubt less due to the different seasons of the year at which they were collected, and the latter to the fact of the Ipswich specimen having a more northern birth-place. That there might be no mistake, the specimen was transmitted to Professor Baird for examination, who kindly compared it with' the type in the Smithsonian Institution, and reports that her found them identical.

1

SAVANNAH SPARROW. Passerculus savanna Bon. Rather rare in the interior at all seasons, and, so far as I can learn, only seen there during its migrations. On the coast, how ever, it is one of the most common sparrows throughout the summer, where great numbers breed. I have seen it from: Ipswich southward all along the coast to Nantucket Island. On the islands off the coast it is often the most numerous species of bird. The Song Sparrow, on the contrary, is more numerous in the interior, it being comparatively scarce on the islands and on the coast close to the sea. '/

HENSLOW'S SPARROW. Coturniculus Henslowii Bon. This species must still be considered a rare summer visitor, though it proves to be more common than was supposed a few years since. Specimens are taken in the eastern part of· the state nearly every year, where also several of its nests.

*See Baird's Birds of North America, p. 441.

have been found. The first nest found in this state was discovered by Mr. E. S. Wheeler, in Berlin, and the fact is recorded in the seventh volume of the Proceedings of the Boston Society of Natural History (page 137). This species was at first wrongly identified as Peucea Backmanii Aud (=P. æstivalis Baird), and as such stands recorded in the sixth volume of the same Proceedings (p. 21). The mistake was corrected, however, on p. 74 of the same volume, so that Peucea æstivalis has never been included nor referred to as a bird of Massachusetts in any of the lists of the birds of the state, or of New England.

In respect to C. Henslevii, Mr. Maynard informs me it has been confounded with C. passerinus by a number of collectors, and that it seems to be more common at some localities in the state than the latter. bas bor

WHITE-CROWNED SPARROW. Zonotrichia leucophrys Sw. Rare in all parts of the state, and thus far not known to breed in Massachusetts, though it may do so among the mountains in the western counties. Though mentioned by Dr. Coues as "usually common, but of somewhat irregular occurrence" in New England,* the score or more of collectors with whom I am acquainted all look upon it as one of our rarest species in Massachusetts. Some have never met with it. More to the westward, however, it is quite com-" mon. In Wayne county, New York, I found it as numerous in May, 1867, as the White-throated Sparrows usually are in New England. lt mai lao) 959 Po eomdei 941 50

i

WHITE-THROATED SPARROW. Zonotrichia albicollis Bon." A pair of these birds, probably the same pair, has been ob-" served by Mr. R. B. Hildreth ht Springfield during the last three summers. Though he has not succeeded in discovering their nost, he this year observed them feeding their scarcely fledged young. He reports that they have become "very familiar and readily answer his call. Though breeding nuatson ali to imezon zle answ ̧vesy znova vuon she oft

List of the Birds of New England, 1. c. p. 282.