358 THE FLOUNDER FAMILY. 



conspicuous, being coiled in the egg-capsule (Plate IV, fig. 14). 

 It is dotted all over the head and body with a great number 

 of little round spots of a bright yellow colour, and less numerous 

 branched black chromatophores which take up a rather more 

 definite arrangement, being somewhat evenly scattered over the 

 trunk but collected together in masses upon the dorsal surface 

 of the head. The eyes at first show a reddish-golden lustre but 

 as development proceeds they acquire the characteristic silvery 

 sheen of the larval and post-larval stages. 



Two days after this the capsule bursts and the larva 

 measuring about 6 mm. (Ehrenbaum gives 7'5 mm.) emerges. 

 The pigmentation does not differ in very essential respects 

 from that of the embryo, but it has assumed a more 

 definite arrangement. The black chromatophores are mainly 

 confined to a dorsal and a ventral row, running longitudinally 

 along the body, with a few scattered stellate spots upon the 

 surface of the yolk-sac; the yellow pigmentation, on the contrary, 

 is still in the diffuse condition, small yellow spots being dusted 

 over the body and marginal fin. Apart from these features, 

 the large size of the larva together with the broad marginal 

 fin are diagnostic. 



Having followed the life-history of the plaice up to 

 this point we may mention the peculiar role which has been 

 assigned to the shrimp in connection with this fish. Day 

 states that the opinion was at one time held that the shrimp 

 was actually a stage in the life-history of the plaice, a piscine 

 larval form in fact, which by a direct metamorphosis gave rise 

 later to the latter. Naturalists did not at first succeed in 

 demonstrating the want of truth in this fable. Deslandes, 

 amongst others, reported that shrimps kept under observation 

 in a vessel of sea-water gave rise, in his opinion, to young 

 plaice, though he did not elucidate the stages in the process. 

 He supposed that the eggs carried about by the parent-crus- 

 tacean below its body were eggs of the plaice, which reached 

 the hatching-stage only when thus taken care of by the strange 

 foster-parent. Lacepede, following up this line of thought, 

 attempted to account for the presence of eggs on the under- 

 surface of shrimps by the suggestion that they adhered to the 



