PALAEMON NIPPONENSIS. 175 



the wrist is 17 mm., the palm 20 mm. and the fingers 14 

 mm. The carpopodite is accordingly somewhat shorter than 

 the arm and the palm , but always longer than the fingers 

 which are never so widely curved as in Pal. ornatus Oliv. 



Palaemon Japonicus de Haan. 



De Haan, Fauna Japonica, Crustacea, p. 172. — von 

 Martens, 1. c. pag. 43. 



This species presents some resemblance to the Indian 

 Pal. ornatus Oliv., but may be distinguished by the shape 

 of the rostrum , four or five of its teeth forming a longi- 

 tudinal series, posterior to the eyes, and by the form of 

 the second pair of legs : the arms being comparatively shorter 

 and thicker , the hands more depressed and the fingers too 

 comparatively shorter. 



It may also be distinguished from Pal. brevicarpus 

 de Haan by the shape of the rostrum and the structure 

 of the second pair of legs : these species are quite different 

 from one another. 



I may be allowed to add the measures of a young 

 male specimen of Pal. .Japonicus De Haan, only 65 mm. 

 in length ; the left leg of the second pair is already some- 

 what greater than the right one, and is 46 mm. long, the 

 arm measuring 8^/3 mm., the wrist 9 mm., the palm 13 mm., 

 and the fingers 7 mm. 



Palaemon nipponensis De Haan. 



De Haan, Fauna Japonica, Crustacea, p. 171. — Palae- 

 man Sinensis Heller , Novara-Reise , p. 119 , taf. X , fig. 11. — 

 von Martens, 1. c. p. 42, 



The length of the rostrum of this species is very vari- 

 able, reaching in some specimens to the end of the peduncle 



Notes from the Leyden IMuseuiii. 



