DEVELOPMENT AND LIFE-HISTORIES OF TELEOSTEAN FISHES. 845 



surface of the body is, however, much more generally studded with pigment-patches and 

 cells, and the touches on the marginal fin are better developed. On the other hand, 

 except a few minute grains along the body-line, the whole left side in some is white. 

 The black pigment-spots in the American flounders, figured so deftly by Alexander 

 Agassiz, show similar features, and the spots described are very generally distributed. 



The difficulties in diagnosing from size alone, are well illustrated in this species. 

 Young forms, captured at different times, measured 9 mm. on the 15th April, 9 to 27 mm. 

 on the 26th April, 15 mm. on the 24th May, 8 to 30 mm. on the 8th June, 10 to 18 mm. 

 on the 18th June, 80 mm. on the 27th June, as well as 40 and 94 mm., while man}'' 

 ranged on each side of three-quarters of an inch. In July from 22 to 32 mm. In August, 

 many captured in sand-pools near the estuary of the Eden were only 12 mm. 



Rhombus maximus, Will. — The ripe ova of the turbot were procured from a female 

 of 12 lbs., on the 10th July, during the trawling expeditions of 1884.* They are very 

 small, only a little larger than those of the rockling, and the embryos, many of which 

 were hatched from pelagic ova of the same appearance, captured by the tow-net on the 

 spot, are likewise small. This seems to have been the first occasion on which ripe eggs 

 of this species had been procured in this country. No oil-globule is present. 



A post-larval form procured in August in considerable numbers, both south-east of 

 the Isle of May and off the Isle of May rocks, is apparently the turbot. The youngest 

 example, the eyes of which are still symmetrical, measures about 6 mm., with a maximum 

 breadth of about 3 mm.t The larval tail projects backward and slightly upward, 

 and is still surrounded by the embryonic fin. It protrudes considerably beyond 

 the inferior fin-rays developed beneath it. The head of the fish is proportionally large, — 

 larger, as compared with the length of the fish, than in any other form examined. The 

 mouth is large. The dorsal line is nearly straight from above the otocysts to the base 

 of the tail, but the ventral line slopes rapidly downward from the tail to the anus, and 

 again rises with an anterior curve to the jaw. Thus the body has a triangular outline. 

 The dorsal and anal fins have rays, and are of moderate length. Papillae indicate the 

 rudiments of the ventral fins. Both surfaces of the body are minutely speckled with 

 black points, but the right is more uniformly marked in this way. The specks extend 

 to the marginal fins, but not over them. 



The changes which follow — as seen in the next older forms — are the slight increase in 

 depth and roundness of the body posteriorly, the elongation of the rays of the marginal 

 fin, and the appearance of five or six touches, caused by aggregations of dots, in the 

 dorsal, the ventral still remaining speckled as before. The closely approximated ventral 

 fins have likewise minute black points, but the pectorals remain pale.J The right eye 

 meanwhile is gradually passing upward, and the embryonic fin is rapidly disappearing. 



* Vide Report, p. 363. 



t The spawning period of the turbot in the Baltic is given as May and June, but in the North Sea, July (Mobics 

 and Heincke). 



X A larval pelagic flounder of Mediterranean (Peloria riippelii, Cocco) has remarkably pedunculate pectorals, a 

 feature present in many young fishes (Emery, Reale Accad. dei Lincei, Glasse di scienze fisiche, math, &c, xiv\, 1883). 



