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Show 542 MR. J. T. CUNNINGHAM ON THE [June 17, 4th, and 5th rays are longer than the 6th, the third being the longest. In a female specimen 20 cm. long the 3rd ray was 14-5 m m . long or two fifths the length of the head. At the same time the 3rd ray in the adult female is not so long as the longest rays of the fin, which are behind the middle of the body and are half the length of the head as in A. laterna, according to Dr. Giinther's description. The longest ray in the left pelvic fin in the female specimen just mentioned was about the same length as the 3rd dorsal, namely 15 m m. In young specimens of either sex less than 13-2 cm. in length, no elongation of the anterior dorsal fin-rays exists, but the rays increase gradually in length from the 2nd backwards. I have now to guard against the possible objection that the large adult specimens I have described are males and females of a distinct species A. lophotes, and the small specimens are A. laterna. The truth of m y conclusion is almost sufficiently established by these facts, that I have examined a large number of specimens taken indiscriminately by the trawl in various localities and at all depths, that among these specimens all those in which the anterior dorsal rays are elongated and thickened are males, all those in which the anterior dorsal rays are very slightly elongated are females more than 13 cm. long, and all specimens less than 13 cm. in length are of either sex and show no elongation of the rays. But all possible doubt is overcome by the fact that with the exception of the three characters already discussed, namely, the length of the anterior dorsal fin-rays, the length of the upper jaw, and the size of the eyes, all m y specimens essentially agree with descriptions given by previous writers of tho species A. latema. To show this I will describe some of the characters in m y specimens. The following are the numbers of fin-rays found in three specimens :- Male 19-3 cm. long .. . .D. 101. A. 78. P. 10. V. 6. C. 17. Female 20 cm. long D. 96. A. 75. P. 10. V. 6. C. 17. Female 10-2 cm. long . D. 92. A. 69. P. 10. V. 6. C. 17. The extreme tenderness of the skin and slight attachment scales are equally exhibited by all the specimens ; in fact all those brought to m e from the deep-sea trawlers have lost the whole of the scales and skin from both sides, except the scales of the lateral hue on the upper side. The membrane of the longitudinal fins also possesses this tenderness, so that the rays are usually much separated in captured specimens. The elongated rays in the male are free for the greater part of their length, and not fringed or bordered with membrane. The shape of the body and o- the lateral line are the same in all the specimens. The bight of the lateral line above the pectoral is almost rectangular. The broadest part of the body is across the end of the pectoral fin, whence the edges curve gradually backwards, more steeply forwards. The anterior extremity of the body is pointed, the mouth-cleft opening at the apex, and the apex being nearer the ventral than tho dorsal edge. |