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ART. II. On the Green-winged Teals of America and Britain. By JAMES DRUMMOND MARSHALL, M.D.

DURING the mania for forming new genera and species which seems at present to exist, when names and distinctions hitherto employed are no longer permitted to occupy the place they formerly held in our nomenclatures, it is strange that even one species should have been allowed to remain in obscurity under a different name; more particularly a species presenting so many distinguishing traits as the green-winged teal of America, the subject of the present remarks.

The similarity between this bird and the common teal of Britain has appeared so great, as to lead Wilson, and other writers on the subject, to consider them as one and the same species. Wilson says, "On an examination of the figure and description of the European teal by the ingenious and accurate Bewick, and comparing them with the present (the green-winged teal), no difference whatever appears in the length, extent, colour, or markings of either, but what commonly occurs among individuals of any other tribe; both, undoubtedly, belong to one and the same species."

Now, it is remarkable that Wilson, who has been in general so accurate an observer of nature, and whose descriptions are so correctly and beautifully given, should in this case have overlooked the disparity between these two birds; a disparity sufficiently great, in my opinion, to constitute them distinct species. On looking at the birds separately, and not having previously compared them, one would be inclined to pronounce them of the same species; but when a specimen of each is laid before you, the markings will be perceived to be in many points totally different. Latham, Forster, Pennant, Bonaparte, and the authors of the Northern Zoology, have mentioned some of the distinguishing marks, but have merely considered the American as a variety of the European, and not a species distinct from it. Sir William Jardine, in his beautiful edition of the American Ornithology, is of opinion that the species are distinct, and has accordingly given the American teal the distinguishing name of Bóschas carolinensis. It shall be my aim, in the present remarks, to show that the American and European teals are in many points totally different; and that Sir William Jardine has, with great propriety, made them, for the first time, distinct species.

In length, extent, weight, and general appearance, they nearly correspond. The crest in the American species is perhaps larger than in the European, and the black extends farther down the throat. The bill is smaller and more

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slender in the American, and the edges of the upper mandible considerably overlap those of the lower mandible. In the American, the white streak is wanting which extends from the bill over the eye in the European; and the white line below the eye is also nearly wanting, being but very indistinctly marked in the American. The beautiful creamcoloured longitudinal band on the scapulars, which is so evident in the European, is totally wanting in the other; while across the shoulder, a very distinct transverse bar of white (about 1 in. long, and three eighths of an inch broad) is noticed, no trace of which is seen in the European.

Now, to me, these marks afford sufficient evidence of the birds not belonging to the same species. When we speak of a variety of a bird, we mean a certain departure from the ordinary structure or plumage of that species; but where so many writers, for so long a period, have noticed a decided difference among the members of what was supposed the same species, we cannot surely longer continue the inappropriate term of variety.

For the better illustration of the subject, I shall accompany these remarks by figures of both the species; and any one who compares them must, I think, be struck with the difference. (figs. 1. and 2.) It is strange that Wilson should have given a figure of the American bird, without the white line extending over the eye, and with the transverse bar on the shoulder, two of the most distinguishing marks, and yet have called it merely a variety of the European; while in Rennie's edition of Montagu's Ornithological Dictionary we find an engraving intended to represent the British species, but which is evidently copied from Wilson's plate, and marked

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with the bar of white in the shoulder, which is never seen in the British teal; thus perpetuating an error, or at least giving a representation of the American bird accompanying the description of the British species. An accurate engraving of the latter may be found in Bewick, similar to the one here supplied.

In the Proceedings of the Committee of Science and Correspondence of the Zoological Society of London, Colonel Sykes mentions the Anas Crécca, or common teal, as being found in the Dukhun, and that his specimens appeared identical with male and female British specimens. He has also in his possession specimens resembling the Anas Crécca, but in which the proportional length of the intestinal canal differs so much from that of the Anas Crécca (3.30 to 1, and 5.57 to 1), that he is induced to believe that they may belong to a distinct species. Now, it would be well worthy of attention, to have the relative length of the intestinal canal of the American species (Bóschas carolinensis Jardine) compared with that stated by Colonel Sykes, lest the teal found in Dukhun may be the same as the American, and not the European, as now supposed.

I do not mean to say that the length of the intestinal canal should be a sufficient datum to constitute a new species, but the difference in plumage may have been overlooked, as has been hitherto done, and the species thus confounded. It seems to me much more probable that the American and Indian species should be the same, than that the American should differ from both the Indian and European, and these latter be similar.

I merely throw out these hints to induce further investigation; and, should they lead some one to pursue the subject farther, they will not have been made in vain.

Belfast, Sept. 20. 1833.

JAMES DRUMMOND MARSHALL, M.D.

SEE, in Vol. V. p. 473., a notice of the occurrence of " vast flocks of teal" in Jamaica, during the cooler months. They are, the writer states, "of the species, I apprehend, named by Gmelin the carolinénsis, or American teal."-J. D.

ART. III. An Illustration of the Structure of some of the Organs of a Spider, deemed the Type of a new Genus, and proposed to be called Trichopus libràtus. By C. M.

Sir,

["Contrivance intricate express'd with ease,
Where unassisted sight no beauty sees."

COWPER'S Retirement.]

resem

I MISTOOK the spider of which I send you a sketch for Pholcus phalangiöìdes, which I had never met with living. The great length of its legs, the cylindric body (fig. 3. q), and the attitude, caused it to bear so considerable a blance to that species, that it was only on carefully examining the eyes and parts of manducation, that I discovered As it agrees exactly with none of the heretofore established genera, I propose naming it

my error.

TRI CHOPUS. (Thrix, hair, pous, foot; legs extremely hairy, the hairs themselves branched, n.) Eyes 8, large, subequal, separated by a considerable interval from the base of the mandibles; placed in two rows, the anterior curving considerably downwards and having the eyes approximated, the posterior curving forwards and having the eyes widely separated, the exterior being placed on a species of tubercle (fig. 3. a b). Mandibles cylindric, cut off very obliquely beyond the middle of their inner side, and presenting a cavity toothed on both sides for receiving the strong curved hook; hairy and spiny (c). Maxillæ strong, rounded externally at the apex, and cut off very abruptly internally, contracted behind the middle, and dilated slightly where they receive the palpi (d). Lip higher than broad, narrowed anteriorly, and with a sinus at the tip which in rest receives the apex of the anterior lip (d). Palpus long, curved downwards; 1st and 2d joints short, 3d very long, 5th long, and 6th in the male elongate pyriform without a hook; spiny and hairy (d'). Cephalothorax circular or broadly oval behind, produced anteriorly. Legs very long and very hairy, with a few spines especially on the tibia; 1st pair (hi), 9 times the length of the thorax; 2d and 4th pair, 7 times; 3d pair, 64 times: tarsus clawed. Abdomen cylindric with 2 long feelers, and short spinnerets. TR. libràtus. (Libratus, balanced; pensile appearance of insect when at rest, p.) Cephalothorax brownish green posteriorly, castaneous anteriorly, with 2 irregular parallel black lines running from the posterior intermediate eyes down the back, terminating half way by joining semilunar patches which occupy the remainder, and which have 3 irregular processes projecting outwards towards the origins of the legs; internally they are shaded off, but rather defined behind the middle thoracic point, which is marked by a minute short line; beneath reddish brown, darker towards the edges, but with a brighter spot opposite the origin of each leg.- Abdomen greenish; lighter in the middle, which is bounded by 2 longitudinal dark

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festooned lines, the basal portions of which, taken together, seem to form 3 triangles surmounting each other, the apices deficient; behind these the central line has a series (four) of small crescents arching backwards. From the external angles of the festooned lines dark patches run outwards and backwards. Beneath concolorous; 4 parallel festooned lines running down the middle and converging towards the spinnerets. Legs greenish, very hairy, the two anterior coxæ and femora [hips and thighs]

castaneous.

Habitat, Kent.

I have never seen more than two males, and, of course, am unacquainted with the female. It bears the closest resemblance in its generic characters to Arànea and Agelèna; but differs in the eyes being nearly equal, in the length of the lip, and in the maxillæ dilated at the apex: the palpi, too, differ considerably. From Clubiòna, to which the ap

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