142 NOTES ON THE llEPRODUCTION OF TELEOSTEAN FISHES 



exact knowledge of the spawning season of the pollack on this coast, 

 but the first young Gadus to appear in the tow-nets seem to connect 

 themselves with older forms, having the specific characters of G. 

 pollachius, so that this fish would appear to be one of the earliest 

 spawners of the genus. 



A smaller larva, 3 mm. in length, hatched from ova taken on the 

 15th February, is described by Mr. Scott as having no pigment at 

 all. The eggs were not measured. I have seen a similar larva, 

 hatched in transmission from the west coast of Ireland, but a yellowish 

 tinge in this specimen may have been due to the presence of yellow 

 chromatophores. It is possible that both these forms may be somewhat 

 abnormal pollack, since the species seems to have but little black pigment 

 as compared with others, although G. minutus has certainly not very 

 much. 



With regard to other ova of Gadus entered in our records I have 

 only to say that they have been provisionally named in accordance 

 with their apparent relationships. The dimensions, where noted, are 

 given ; the same remarks apply to the later stages, with which it is 

 proposed to deal more fully when sufiicient material has been 

 accumulated. 



Motella. — The Eocklings. 



Our records comprise a great number of eggs which can be referred 

 with certainty to the genus Motella. I do not think it is at present 

 possible to identify them, in all cases, with any particular species. Ova 

 directly derived from M. mustela and M. tricirrata have been described 

 by Brook and M'Intosh and Prince (ilf. mustela) and by Eaffaele {M. 

 tricirrata). The descriptions do not, however, materially assist us to 

 distinguish tow-net specimens, since the observed differences of dimen- 

 sions might easily be obscured by variation in this respect. It is well- 

 known that the newly extruded egg has usually a number of oil-globules 

 which subsequently fuse into one. In the case of both the species 

 mentioned the ova hitherto described as directly derived from the 

 parent showed no colouration of the oil-globule. Eaffaele, nevertheless, 

 identifies with M. tricirrata a tow-net egg, having an oil-globule the 

 colour of olive-oil. It is quite possible that this identification is correct, 

 since the oil-globules of Solea (and Trachinus?) do not acquire their 

 characteristic colouration until some time after extrusion. Other forms, 

 which need not be recapitulated, give rise to ova in which the globules 

 are coloured even before the egg is ripe, but this is not necessarily a 

 constant feature. Thus from different females of Trujla cuculus and 

 Caran): trachurus I have pressed ova of which the globules showed 



