igiy. 



S. Kemp : Notes on Crustacea Decapoda. 



299 



ated further to the north-east belong to the subspecies improvisa 

 and it appears, therefore, that the northern distributional limit of 

 the typical form is somewhere in the vicinity of Lake Biwa. The 

 specimens recorded by Miss Rathbun from the latter locality un- 

 doubtedly belong to the typical form and this is perhaps also the 

 case with the solitary individuals which she examined from Tsus- 

 hima I. and from Fusan in Korea. If my views on the distribu- 

 tion are correct, Balss' examples from Koitogawa in Kadzuza prov. 

 are to be referred to the subsp. ivtprovisa, while those recorded 

 from Okayama belong to the typical race. Balss notes that in the 

 latter individuals the eggs are 0*63 mm. in length and 0*40 mm. 

 in breadth. 



Dr, Annandale noted that the species was abundant among 

 weeds or dense vegetation at Komatsu and in pools and back- 

 waters round Lake Biwa ; in the lake itself it was much scarcer. 

 Living specimens showed no definite markings, but were dotted 

 more or less profusely with small pigment cells. The fingers of 

 the chelae were tinged with orange brown. The Temnocephaloid 

 worm Caridinicola was present in the gill-chambers of a large pro- 

 portion of the individuals examined at Komatsu. 



subsp. improvisa, nov. 



1868. Atyephyva compressa, von Martens, Arch. f. Naturgesch., XXXIV, i, 



p. 51, pi. i, figs. 4a-c. 

 1882. AtyepJiyra ? compressa, Miers, Aiui. Mag. Nat. Hist. (5,, IX, p. ig,^. 

 ? 1890. Miersia compressa, Ortmann, Zool. Jahrh., Syst., V, p. 464. 

 ? 1902. Xiplwcaris compressa, Dottein, Abhandl, matli.-pJiys. . Klasse K. 

 Bayer. Akad. Wiss., XXI, p. 632. 



This subspecies is distinguished from the typical form almost 

 entirely bv the dentition of the rostrum. The rostrum reaches to, 



Fig. 2. — Paratva compressa subsp. improvisa nov. 



a. First peraeopod. d. Dactylus of third peraeopod of female. 



b. Second peraeopod. e. Fifth peraeopod. 



c. Third peraeopod of female. /. Dactylus of fifth peraeopod. 



or a Uttle beyond the antennal scale and bears on its upper margin 

 an uninterrupted series of 7 to 18 (usually 8 to 15) teeth. The 



