280 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [56] 



aa. [Dorsal rays, 124; anal ray3, 100 ; scaler of bliud side scarcely ctenoid, 30-105-325 

 snout and lips not scaly ; maxillary 3 in head ; eyes, large, 2| in head, separated by 

 a very narrow ridge; head 4^ iu length ; depth about 3 ; light brownish gray, the 

 fins dusky, the pectoral black. ] ( Goode $• Bean) Atrimana, 65. 



64. MONOLENE SESSILICAUDA. 



Monolene sessilicaiida Goode, Proc. U. S. Nat Mus., 1330, pp. 337, 338 (deep sea south 

 of New England). Goode, Proc. U. S. Nat. Mus., 1830, 472 (deep sea south- 

 ern coast of New England, stations 870, 871, 876,. 877). Jordan & Gilbert, 

 Syn. Fish. N. A., 1832, p. 841. Goode and Bean, Bull. Mus. of Comp. Zool- 

 ogy, xix, p. 184 (station 314 ; South Carolina). 



Habitat. — Deep waters of the Gulf Stream. 



This species is known to us from the accounts of Goode & Bean. 



65. MONOLENE ATRIMANA. 



Monolene atrimana Goode & Bean, Bull. Mus. Comp. Zool., xii, 155, 1386 (deep 

 waters off Barbadoes). 



Habitat. — Deep waters of the Caribbean Sea. 



This species is known to us from the original description. 



Genus XXV.— OXCOPTERUS. 



Oncopterus Steindachncr, Ueber eine neue Gattung und Art aus der Familie der 

 Plenronectoiden, 1874, 1 (darwini). 



Type : Oncopterus danvini Steindachner. 



This singular genus is based on a single species found on the shores of 

 East Patagonia. It has no near allies among the American flounders, but 

 it has several points of resemblance to the genera Rhombosolea, Ammotre- 

 tis, and Peltorha\nphus of the Australian fauna, and we have ventured to 

 associate the four in a subfamily, which may be called Oncopterinw. The 

 Oncopterinm agree in having some sort of peculiar appendage on or near 

 the snout, apparently connected with the first interspinal. They agree 

 with the Platesslnce in the general form, the dextral portion of the eyes, 

 and in the structure of the mouth. Their nearest ally in this group is 

 Pleuronichthijs. In the insertion of the ventrals, they agree with the 

 Pleuroneclinm and with the genus Achirus of the Soleinw. In both 

 Peltorhamphus and Rhombosolea, the ventral is continuous with the anal 

 as in Zeugopterus and Achirus, but iu Oncopterus the two fins are sepa- 

 rate. In Peltorhamphus and Rhombosolea, the bone connected with the 

 the first interspinal extends forward as a sort of nose, meeting the chin 

 (much as in Achiropsis aud Apionichthys). Iu Oncopterus this bone is 

 twisted to the blind side, and has a very peculiar position, described 

 below. The scales are smooth and cycloid in Oncopterus aud Rhombo- 

 solea, ctenoid in Peltorhamphus. In Peltorhamphus aud Oncopterus the 

 left ventral is present. It is wanting in Rhombosolea. Ammotretis we 

 have been unable to examine. Iu Oncopterus the lateral line has an an- 

 terior arch and many accessory branches. It is straight aud simple in 

 the other genera. In all the teeth are sharp, close set, iu a baud, and 

 chiefly on the blind side. 



