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Show 1868.] NOTES ON HEPTRANCHUS INDICUS. 371 Comparison of the two Sharks, with their points of difference. Galeocerdo tigrinus as given in Galeocerdo rayneri as figured Midler and Henle. and described in the present paper. 1. Frontal elevation of doubt- 1. No frontal elevation. ful character. 2. A hazel eye. 2. Iris bronzed silver. 3. A warm brownish tint ex- 3. Head, upper surface of tending over the head and upper back, tail, and fins bluish grey, surface of body and tail, with without oblique marks extending oblique streaks extending to the to the gill-openings or under the gill-openings and under the throat. No warm brown tint ob-throat. servable anywhere. 4. Upper lobe of tail, from 4. Upper lobe of tail, from tail-pit * to extremity, over a tail-pit to extremity, a little more third of the whole length of the than one-fourth of the whole fish. length of the fish. 5. Lower lobe of tail less than 5. Lower lobe of tail nearly one-third the length of the up- half the length of the upper. per-j\ DESCEIPTION OF PLATE XXXII. Fig. 1. Eepresentation of the recent fish. 2. Portion of skin, magnified about 20 diameters. 3 a. Upper jaw. b. Lower-jaw teeth. 4. Inferior aspect of the head. 5. The nostril, with blunt triangular flap. 6. Notes on Heptranchus indicus, chiefly as regards Sexual Characters. By J. D. M A C D O N A L D , M.D., F.R.S., and Mr. C H A R L E S B A R R O N , of the Haslar Museum; with Drawings from Nature by Dr. M A C D O N A L D. (Plate XXXIII.) The subjects of the present paper, male and female of Heptranchus indicus, were taken by F. M. Rayner, Esq., Staff-Surgeon, R.N., in Bass's Straits, in January 1858 ; and in addition to the beautifully preserved jaws, portions of skin, &c, he made accurate notes of all the principal characters, with the dimensions and colouring as observed in the fresh state; and these remarks we transcribe in extenso:- The head flat, with minute spiracles placed behind the eye, near the top of the head, and vertical to the corner fold of the mouth ; * N o inferior tail-pit is given in this figure, nor in that of G. arcticus. t Though two notches are given near the extremity of the upper tail-lobe, no distinct terminal lobe is represented. |