THE FLAT-FISHES 231 



and takes place between March and May inclusive, a female 

 of 1 8 in. having been computed to contain not far short of 

 half a million eggs. 



The egg measures less than -J^ in., and has a single oil- 

 globule. The surface of the capsule is covered with ridges 

 and punctures, resembling, therefore, the egg of the brill. 

 Hatching takes place, in spring temperature, on the fifth or 

 sixth day, and the larva is dotted with black, yellow spots 

 appearing on the fourth or fifth day. In a fish of rather less 

 than \ in. the transformation is almost complete, but there 

 are as yet no scales. These first appear at the tail end, when 

 the fish is rather over an inch long, and do not extend over 

 the rest of the body until the fish is 2 in. 



The Scald-fish {Arnoglossus * laternd)^ or Scald-back, derives 

 its vernacular name from the scalded appearance of the body 

 when the fragile skin is roughly handled and in consequence 

 peels off. Even the action of the trawl, and the contact 

 with debris in the net, suffices to produce this effect. 

 Although the skin is so thin, the scales are rough and 

 spinous, though in a lesser degree than those of some 

 flat-fishes already described. This roughness is confined to 

 the upper side, on which also the scales are larger than on 

 the lower. This is the only British flat-fish in which there 

 has so far been any recognition of secondary sexual characters, 

 of which several examples have in previous chapters been 

 given in connection with the round fish. The male has the 

 first rays of the dorsal fin (which has in all from eighty- 

 seven to one hunded rays) elongated ; but this character is 

 not seen, save to a very small extent, in females, and is quite 

 wanting in young males. Nor is it actually associated in 

 adult males with maturity, since that stage may precede it by 

 a considerable time. The mouth of the scald-fish is almost as 

 small as that of the plaice, the teeth being, as in the rest 

 of the present group, equal on both sides. 



* Prof. Mcintosh prefers Platophrys. 



