242 



Part III. — Sixteenth Annual Report 



crassicomis*). Twenty of tliis species were found in the stomach of a 

 plaice of 15mm. 



Several parasites that infest the young flat-fish have been mentioned by 

 Professor M'Intosh.t Several specimens of a species different from 

 those mentioned by him were found adhering to the pectoral region, 

 ventral and dorsal, of the young plaice and flounder, probably brought in 

 from the sea.J 



The largest of the plaice taken from the harbour and burn was 22mm.; 

 they migrate about that size back into the salt water. Specimens 

 from three to four inches were obtained close to the rocks by the pier. 

 It is possible, however, that even at this early stage they begin their 

 northward migration. § At the mouth of the Eden they are obtained of 

 a size from 12mm. to nearly 4 inches during May to September. The 

 rate of growth of the plaice has been sketched by Masterman. [Foot- 

 note Thirteenth Annual Report Fishery Board for Scotland, Part III., 

 p. 289.] 



* T. Scott, lOth S.F.B. Report, p. 250. 



t " Researches," p. 843. 9tli S.F.B. Report, p. 330. 



X On these Mr. Caiman, B.Sc, to whose kindness I am much indebted, has made the 

 following note : — 



The three specimens sent are the Praniza or larval form of a species of Gnathia 

 which I have not been able to identify. It differs from the common Gnathia 

 maxillaris Mont., and, indeed, from all the forms described in Spence, Bate, and "West- 

 wood's British Sessile-eyed Crustacea, and in Sar's Crustacea of Norway, vol. ii., in 

 the short and rounded telson, which is much shorter than the inner plates of the 

 mopods. I have compared the specimens with a series in the Museum of University 

 College, comprising many stages of both sexes from different parts of the British 

 coasts, and have found none to at^ree with them in this respect. It is almost 

 impossible, however, to determine the species with certainty until the adult forms 

 have been found. The occurrence of a species of this genus in fresh (or brackish) 

 water is a very interesting, and, so far as I know, a new observation. 



W. T. C. 



University College, 

 Dundee, 28th October 1897. 

 § Migrations of the Food-Fishes. Dr. Fulton, 11th S.F.B. Report, p. 176. 



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