110 NOTES ON THE REPRODUCTION OF TELEOSTEAN FISHES 



lin. I caunot count the rays of the dorsal and anal in any of my 

 specimens ; they are not fully developed, but seem in general agreement 

 with the adult formula. As regards the fiulets, judging from my best 

 specimens, each isolated basal lobe bears at its apex a single stout 

 somewhat fan-shaped ray, divided distally into numerous fibres. The 

 caudal is injured in most of my specimens. It appears to be slightly 

 forked, as in Fig. 3. Small dark chromatophores are present on nearly 

 all parts of the head and trunk. Larger chromatophores occur on the 

 top of the head and along the dorsum, especially along the base of 

 the second dorsal and dorsal finlets, while there is a corresponding 

 ventral band at the base of the anal fm and finlets. The sides and 

 under-surface of the abdomen are somewhat silvery. On the sides of 

 the trunk the chromatophores are set more thickly at the lines of 

 division of the myomeres than elsewhere. I never saw these large 

 specimens in the fresh condition. As I received them, a few days after 

 they were placed in alcohol, they appeared to have been of a general 

 bluish-grey colour, with silvery eye, gill-cover and abdomen. 



Caranx trachurus. Linn. Scad, Horse-mackerel. 



Holt, E. W. L., Journ. M. B. Assoc, N.S., iii., 1894, p. 190. Ripe ovarian egg. 

 (I) M'Intosh, W. C, Eleventh Ann. liep. S. F. B., 1893, p. 245, PI. IX., fij,'. 8. 



Unidentified egg, 1"2954 mm. in diameter. 

 Holt, E. W. L., Annales du Musee de Marseille, 1898. Egg, larvce, various stages 



of metamorphosis. 



My previous communication on the reproduction of this species 

 dealt with ova obtained from dead North Sea specimens. Though 

 milt was added to the water into which the female fish were stripped, 

 I do not think that the eggs were fertilised, since the expansion of 

 the zona and the development of the protoplasmic mound, which I 

 then described, is often if not always achieved by ripe ovarian eggs 

 without any aid from the male product. The observation served to 

 demonstrate the pelagic nature and extreme buoyancy of the egg, 

 and the complete segmentation of the yolk. 



At the time of writing I had not access to Agassiz and Whitman's 

 memoir on the " Pelagic stages " {Mem. Mus. Comp. Zool. Harv., xiv., 

 1885, p. 12, ris. IV., v.), and erroneously asserted that the scad 

 furnished the only instance of an Acanthopterygian egg with completely 

 segmented yolk. As a matter of fact these authors have given a 

 beautifully illustrated account of the egg of Tcmnodon saltator, a 

 Carangoid allied to Caranx, and their figures sliowing the gradual 

 phases in the segmentation of the yolk are probably ecjually applicable 

 to the scad, in which I was able to note that the formation of the 

 yolk spherules is accomplished, at least in part, after the deposition 



