DEVELOPMENT AND LIFE-HISTORIES OF TELEOSTEAN FISHES. 835 



upper lip is longer, as also is the barbel on the mandible, while the snout is less pro- 

 longed, the latter character being indicated by Mr Day. These examples measured 

 27 and 38 mm. respectively, and corresponded with Motella cimbria. 



Unknown Egg with Oil-Globule (f). — A small egg, measuring '034 by "035, with a 

 single oil-globule, and in the earlier stages agreeing with Motella, was captured by the 

 trawl-like tow-net on the bottom in the early part of May and for some time thereafter. 

 As soon, however, as the pigment appeared in the embryos its distinction from the 

 common species (M. mustela) was evident (PL V. fig. 4). The reticulated cellular 

 appearance of the contained embyro and yolk was another marked feature. 



After extrusion the larva (PL XVII. fig. 4) measured about T Vth of an inch, and was 

 characterised by the presence of yellowish pigment along the marginal fin dorsally and 

 ventrally, blackish chromatophores occurring amongst the rest. The tip of the tail, how- 

 ever, remains uncoloured. The general surface of the body, head, and yolk-sac is dotted 

 with yellowish pigment, and a few black chromatophores are present on the yolk and oil- 

 globule. No pigment appears in the eyes. The oil-globule is situated inferiorly distinctly 

 behind the middle of the yolk-sac, but a considerable interval exists between it and the 

 posterior border of the latter, thus distinguishing it at once from the egg of Motella 

 mustela. Moreover, the entire surface of the larva is covered with a somewhat coarse 

 reticulation of cells with nuclei, which do not occur in the centre of the cells, but at their 

 margins. On the third day after hatching the mouth had not yet opened, and the only 

 new feature was the more general distribution of the yellowish pigment. 



This larva was kept until the yolk and oil-globule had wholly disappeared. The 

 chief change was the more conspicuous nature of the yellow chromatophores along the 

 margin of the dorsal fin. The head is of a deeper yellow from the pigment over the 

 brain, and the hoc\.j has many minute yellow chromatophores mingled with black. The 

 pectorals are tipped with yellow, and have the streaked mesoblastic basal region. The 

 eyes are greenish silvery. The mouth is widely open. At this stage it somewhat 

 resembles a pleuronectid. 



An unknown larval fish (e) procured in February, and elsewhere # described and 

 figured, approaches the preceding group (Gadoids) in the large size of the silvery eyes, 

 which abut close on the maxillary border. At 10 mm. the notochord is straight, and 

 embryonic rays occur in the tail. A marginal fin occurs along the ventral edge of the 

 abdomen, which has a small yellowish oil-globule beneath the liver in front. Five black 

 chromatophores occur over the head. 



Young Pleuronectid^. 



Hippoglossoides limandoides. — The long rough dab seems to spawn early in the 

 season, for during the trawling expeditions ripe specimens occurred towards the end of 

 March ; and some seemed to have discharged all their ova on the 21st March. Com- 



* "Pelagic Fauna," Seventh Annual Report, Fishery Board for Scotland, 1889, p. 263, pi. iii. figs. 5-7. 



