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Show 82 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. d f the mouth s1· m1'1 ar t o th a t of the M.• labeo of the Mediterra. nean. Lips Form an appearance o 1 d 'th th borders fringed. the lower one partially reflexed. fl h d ery much deve ope , WI e ' . . es y, an v 1 h Sul)orbital with a shallow notch on 1ts antenor mar- A tl 0 trace of teet 1 anyw ere. . pparen Y n . t . ngle and obsoletely denticulated. Maxtllary slender · bl' 1 truncated at 1ts pos er10r a • gm, 0 Ique Y 1 d b th the suborbital but showing a little beneath it, from d r btl b t nearly concea e enea ' an s tg Y . en ' Th h d . l'ttle less than one-fifth of the entire length: the snout 1't being a tnfle longer. e ea IS a 1 . f . . s L 't a· 1 diameter of the eye con tamed three and a-hal times m 8 hort and rather obtuse. ong1 u ma . · ' d of any adipose veil. Orifices of the nostrtl approxlmat-the length of the hea : no appearance . h b d t be accurately ascertained, but 1t appears to have been about in The depth oft e o y can no . . g. · 1 th Th ommencement of the anal is but very little m advance of that one-fifth of the entire eng . e c . P of the second d orsa1 ; b ot h fi ns app ear to have been covered w1th small scales. ectorals not qm·t e so 1o ng as th e h ea d.. a pparently no elongated scale abo. ve them: one, however, above the ventrals, half the length of those fins. The fin-ray formula 1s as follows :- D. 4-1/8; A. 3/9; C. 14; P. 16; V. 1/5. The length of this fish is eight inches. DAJAUS DIEMENSIS. Riclta1·ds. Dajaus Diemensis, Ricltards. in Proceed. of Zool. Soc. 1840, P· 25. This genus, which was established by Cuvier and Valenciennes, di~ers from Mugil principally in having vomerine and palatine teeth.: the st~out also IS rat~er more produced, and the mouth less chevron-formed. The~e IS but one s~ectes described in the " Histoire des Poisssons,'' which is found m fresh water m the Caribbee Islands. Dr. Richardson has briefly noticed a second from Van Diemen's Land, in his recent description of a collection of fishes from that country, in the" Proceedings of the Zoological Society." Mr. Darwin's collection contains a specimen of this genus from King George's Sound, which, having reason to think it might be the same as that described by Dr. Richardson, I sent to this latter gentleman, requesting him to compare them. This he obligingly did, and informed me in his answer that he could detect no differences between them, beyond what might be the result of the different manner in which they were preserved, his own specimens being in spirits. and Mr. Darwin's dried. I forbear giving a detailed description of this species, as one by Dr. Richardson will appear shortly in the Transactions of the Zoological Society ; and Mr. Darwin's specimen is in such a bad state of preservation, as hardly to admit of an accurate description of' it being taken. I may just allude, however, to some of its more striking peculiarities. It appears to differ from the D. monticola of Cuvier and Valenciennes in having the teeth in the lower jaw, if they really exist, so minute and thinly scattered as to be scarcely perceptible those in tile upper jaw, however, are very distinct; so likewise are the vomerine and palatine bands. There are also some very obvious teeth on the tip, and at the sides of the tongue, though few m FISH. 83 the middle: this part is said to be without any asperities in the D. monticola. The suborbital is more rounded off at the lower angle anteriorly, and the denticulations thereon rather more numerous and better developed. The scales on the body, those especially above the lateral line, have a few minute teeth on their free edges, communicating a roughness to the touch ; a character not alluded to in the description of the D. monticola, and which therefore may be presumed absent. There are also three more rays in the anal, and one in the second dorsal. The depth of the body in this specimen, from its bad state of preservation, cannot be ascer· tained ; but the head is contained about four and a-half times in the entire length. The diameter of the orbit is one-fourth the length of the head ; and there is nearly one diameter between it and the end of the snout. The jaws are nearly equal, but when the mouth is closed, the upper one projects a trifle; this last is also moderately protractile. The maxillary retires beneath the suborbital. The fin-ray formula is as follows:- D. 4-1/9; A. 3/12; C. 14, &c.; P. 15; V. 1/5. There is but one individual of this species in the collection, which measures seven inches in length. The colours do not appeal,' to have been noticed. FAMILY .-BLENNID..iE. BLENNIUS PALMICORNIS. Cuv. et Val. Blennius palmicornis, Cuv. et Val. Hist. des Poiss. tom. xi. p. 159. The Blenny, which I have referred above to the B. palmicornis of Cuvier and Valenciennes, seems somewhat intermediate in its characters between that species and the B. pa1·vicornis of the same authors. This inclines me to suspect that the two species are not really distinct, as those authors themselves seem to have thought possible, though they state that they never received the B. palmicornis, except from the Mediterranean.• In this specimen the head is one-fifth of the entire length, and the ventrals one-eighth, which is worth noticing, because it is stated that in the B. palmicornis the head is contained nearly five and a-half times, and sometimes nearly six times in the total length; and the ventrals nea1~y ten times in the same. The filaments above the eyes, however, are similar to those of the species just mentioned; quite as much developed, and each divided nearly to the base into five or six flattened bristles. There are about forty teeth in the upper jaw, and twenty-eight or thirty in the lower : the canine below iR very distinct, but above it is almost, if not quite wanting. The fin-ray formula is as follows:- D. 11 /21; A. 21; C. 11, &c.; P. 13; V. 2. The length of the specimen is nearly five inches. The anal is marked and coloured exactly as described to be the case in the B. palmicornis. This species was obtained by Mr. Darwin at the Cape Verde Islands. • According to Mr. Lowe, however, the B. palmicornis is common at Madeira, (see Proc. of Zool. Soc. 1829, P· 83), and a specimen received from him, undoubtedly belonging to that species, is in the Museum of the Cambridge Philosophical Society. |