346 THE FLOUNDER FAMILY. 



yellowish pigment along the marginal fin dorsally and ventrally, 

 blackish grains occurring amongst the rest. The tip of the 

 tail, however, remains ti'anslucent. The general surface of the 

 head, body and yolk- sac is dotted with yellowish pigment, and 

 a few black chromatophores are jDresent on the yolk and 

 oil-globule. No colour appears in the eyes. The oil-globule is 

 placed inferiorly — distinctly behind the middle of the yolk-sac, 

 but a considerable interval exists between it and the posterior 

 border of the latter. Moreover, the entire surface of the larva 

 is covered with the somewhat coarse reticulations formerly 

 alluded to. The posterior end of the gut in some does not 

 extend to the margin of the fin. On the third day after 

 hatching the mouth has not yet opened, and the only new 

 feature is the more general distribution of the pigment. At 

 first the latter does not enter the marginal fin, but by and by 

 it does so. Two slight folds of skin from the oil-globule forward 

 on each side of the yolk are occasionally seen. The notochord 

 is multicolumnar. 



The larval fish was kept till the yolk and oil-globule had 

 disappeared. The chief change was the more conspicuous 

 nature of the yellowish (gamboge) hue along the margin of the 

 dorsal fin, which has greatly increased in depth. The head also 

 assumed a deeper yellow hue from the pigment over the brain, 

 and the body was covered with many minute yellow chromato- 

 phores mingled with black. The breast-fins were small and 

 tipped with yellow, and had streaked basal regions. The eyes 

 were greenish silvery. The mouth was now widely open. The 

 space between the rectum and the yolk was marked. 



In the Researches, a post-larval form not uncommon in deep 

 water, especially south-east of the Isle of May in August, was 

 described, but its relationships were somewhat uncertain, though 

 it was then considered to belong to a sinistral flat fish (pleuro- 

 nectid). Holt' and one of us- have since re-examined it, and 

 we are inclined to relegate it to the topknots. The earliest 

 stage is about 6 — -7 mm. in length (Plate XIV, fig. 4). The 

 head is large, and the gape is even more so, the eyes small, and 



1 Trans. R. Dubl. Soc. v. ii., 1893. p. 104. 



2 W. C. M. Wth Ann. Sept. S. F. B., 1892. p. 274 &c. 



