334 THE REPRODUCTION OF TELEOSTEAN FISHES 



Raffaele's ova are thus smaller than those which we have seen at 

 Plymouth, and have a smaller oil-globule. This difTerence may perhaps 

 be correlated to the size of the parent fish (as noted by one of us in the 

 case of another species*), but llalfaele does not mention the dimensions 

 of the Naples spawuers. The Plymouth female measures about 28 

 inches, 70*2 cm., so far as we can judge. It is impossible to catch her 

 without emptying the tank, a proceeding at present inconvenient. 

 Bass, according to Eissof and Faber;]:, grow, or used to grow, to a larger 

 size than this in the Mediterranean and Adriatic, but Kaffaele's examples 

 may have been smaller. 



The ova of the bass being easily recognisable, whether from the 

 dimensions and proportionate size of the oil-globule, or from the 

 pigmentation of the embryo, as described by Eaffaele, it is somewhat 

 remarkable that they should never have been found in British waters. 

 Eaffaele suggests that spawning may take place indifferently in either 

 fresh or salt water, the ova in the former case developing at the 

 bottom. In this district and at Newquay, young bass, from about 

 two inches upwards, are found in the estuaries, and not, so far as 

 we know, in the open sea, and we have taken a large female, with 

 advanced ovaries, in the Tamar estuary. If spawning takes place in 

 the estuary it is not remarkable that the ova should have escaped 

 notice. Those deposited in the Plymouth tanks floated buoyantly in 

 the Aquarium water, which is of somewhat lower specific gravity than 

 that of the open sea, while Eaffaele seems to have obtained all 

 his specimens, other than those from the Naples tanks, at the surface. 

 Experiments which he describes suggest that perfectly fresh water 

 is deleterious to the ova (of parents that have been living in sea- 

 water ?), while brackish water is rather beneficial than otherwise to 

 the larvse, and does not injure the ova. As has been indicated by 

 one of us,§ Motella mustela, a fish with typically pelagic eggs, almost 

 certainly spawns to some extent in the Plymouth estuary. The local 

 fishermen strenuously assert that the same is true in the case of the 

 flounder, and may be quite correct in their opinion. It is, therefore, 

 by no means impossible that the spawning of the bass takes place, 

 in so far as concerns this district, rather in the estuaries than in 

 the open sea. 



Observations of spawning in an Aquarium give no reliable evidence 

 as to the spawning season under natural conditions, since when both 

 periods have been noted they have not been found to coincide. Our 



* Joimu M. B. Assoc., N.S., v., 1897, pp. 113 and 117. 



t Ichth. Nice, p. 300. 



:J: Fisheries of the Adriatic, p. 71. 



§ Joura. M. B, Assoc, N.S., v., No. 2. 



