378 DEEP-SEA FISHES OP THE ATLANTIC BASIN. 



The glll-openiugs are rather wide, the branch iostegal membranes arc largely developed, 

 with robust rays; the opercular bones are smooth and very thin; the branchial cavities 

 contain four complete arches. The sjjecimens are so very fragile that 1 did not dare to pursue 

 my investigations further. 



The fins are those of an Anacanthine fish, but I could not see any transverse articula- 

 tions in the first ray of the first dorsal; they are not very distinct on the otlicr median fins 

 except on the caudal, the oidy fin with slightly bifid rays; in the other fins the rays are 

 simple; at the base of the long dorsal and anal fins the projecting heads of the intersjjinous 

 bones give I'ise to a serrated appearaiuie. Tlie first dorsal is sniidl, but quite detachcMl from 

 the second one in the two larger s]>ecimens; it rises just above the insertion of tlu^ i>eeto- 

 rals; its second ray is the longest and equals in height the commencement of the second 

 dorsal fin. This is greatly develoi)e(l and maintains a nearly equal line throughout, but as 

 the body tapers toward the tail the fin increases in height in equal ratio. In size, shajjc, 

 and development the anal is the exact counteri)art of the second dorsal fin. The caudal 

 fin is quite distinct, its contour is lanceolate in the smaller specimen, nearly oval in the 

 older one, subtruncate with rounded edges in the oldest or biggest sjiecimen. The pectorals 

 are distinctly lobate, which character is more marked in the smaller specimens; they arc 

 of moderate size and broadly oval in contour. The ventrals certainly give the most striking 

 feature to this singular fish; they are inserted below and in front of the pectorals, at the 

 base, and on each side of the great abdominal cone. They are of great size, and the very 

 robust rays, 5 in number, are all elongated and considerably exceed the intervening mem- 

 br.ane, which only unites their basal portions; the internal and external rays are consider- 

 ably less developed than tlie three median ones, the internal one is the shoitest; both are 

 simple and without any trace of terminal dilatations. The three median rays all terminate 

 in a large beaiitiful lanceolate leaf like blade, through winch, however, the ray continues 

 to the pointed extremity; they are all prolonged beyond the two first-mentioned rays, but 

 the outer one is considerably shorter than the other two; it is smooth and its terminal blade 

 is smaller. The third and fourth rays, counting from the outer one, are siibequal, and bent 

 backwards extend very nearly to the root of the tail; at about the basal third of their 

 length they both present a singular angular dilatation, whicli looks like a thickened articula- 

 tion, but which is merely, so far as I can make out, a membranous dilatation. The great lan- 

 ceolate terminal blades are very large, being little less than one-fourth of the total length 

 of the ray which supi)orts them; their edges are sinuous and they terminate in a fine ])oint. 

 Judging from their length, strength, and development, these ventral paddles must be most 

 eflicieut for swimming; I know of no other fish possessing anything like them, and have, 

 therefore, thought pioper to derive from so peculiar a character the generic name which I 

 have proposed for this singular fish. 



The next remarkable feature of my Uretmophorus is the huge abdominal cone, the base 

 of which occupies the entire space between the insertions of the ventrals and that of the 

 anal fin. This cone appears to deyeloi) with age. and it is certainly largei- and more prom- 

 inent in my oldest and biggest specimen, equaling in height that of the body just behind 

 the pectorals, where it is greatest. This abdominal cone is quite smooth; its skin, devoid 

 of scales, is silvery. 1 have not ventured to open it in any of the three specimens yet dis- 

 covered, for fear of damaging to a certainty these rare and very delicate creatures; but 

 the supposition that it contains most of the alimentary canal can not be far from the trutli ; 

 atits apex, which becomes cylindrical, is an aperture, evidently the vent, and behind this 

 a slender conical pajnlla (Ui which I could not distinguish anything like aiio])cning. 



The scales cover the whole body except the head and abdoujinal cone, which are, as I 

 have said before, naked. They are small, very adherent, cycloid, and maiked with (!on- 

 centric lines. 1 have figured a few magnified (pi. xxxiv, fig. 1), to give an exact idea of 

 their charactei's ; they are very similar to those oi Hmmrhiinclius hcpaticiis, Facciola. A 

 thin pellucid epidermal layer covers them. 



Only three S])ecimens of Erelmiiphiriai Klrhienbeij/i have, so far as I know, yet been cap- 

 tured and preserved; they were cauglit alive with a hand-net along with other jK-lagic an- 

 imals ou the surface at the mouth of the harbor of Messina as the current was flowing in. 



