308 8 



than the carapace; palm so swollen as to be subglobular; fingers almost as long 

 as palm, their opposed edges meeting. 



Dimensions. — Length of c?, 2 mm., width 22 mm. 



Persephona fugax (Fabricius). 



Mijra fugax Alcock, LXV, 202, 1896. 



South of Koh Bidang, 9 fath., mud, shells; I. 18; 1 ?. North of Koh Kut, 10 

 fath.; I. 23; 1 c?. 4— 6 miles S. of Koh Samit, 14-18 fath.; II. 1 ; 1 ?. Koh Kahdat, 

 5—8 fath., sandy mud; II. 16 and III. 4; 2d'- Between Koh Chuen and Koh Chang, 

 15 fath., mud; III. 3; 1Ç with Rhizocephalid parasite in abdomen. 



Persephona pentacantha (Alcock). 



Mi/ra pentacantha Alcock, LXV, 204, 1896. 



Singapore, 2—3 fath.; XII. 4; 1 Ç juv. Koh Kahdat, 5—8 fath., sandj' mud; 

 II. 16 and III, 4; 1 Ç mature. Tung Kaben, 6 fath., sand, mud, phanerogams; II. 

 22; 1 $ immature. 



The measurements of these 3 females are as follows: — Singapore, length 

 9'8 mm., without spine 8 mm., width 78 mm. Koh Kahdat, length 171 mm., with- 

 out spine 14-9 mm., width 137 mm. Tung Kaben, length 219 mm., without spine 

 19 mm., width 171 mm. 



The series indicates that the species is distinct from P. fugax. The two smaller 

 females have the characters given by Alcock. The largest one, not adult, difi"ers 

 from the smaller ones in being less rough, in having the spinule of the postero- 

 lateral margin and those of the antero-lateral margin reduced to large granules as 

 in adult fiigo.v. This species differs from P. fugax in lacking the fringe of hair 

 along the inner pari of the apposed edges of the external maxillipeds. 



Persephona affinis (Bell). 



Myra affinis Ai.cock, LXV, 205, 1896. 



Koh Kam, 5 fath., gravel; II. 6; 1 ? juv. Between Koh Mesan and Koh Chuen, 

 15 fath., stones; II. 6; 1 c?. Between Koh Rial and Koh Mesan, 3—5 fath., sand, 

 algæ; II. 7; 1 ? juv. Gulf of Rayong, 7-10 fath., sand, mud, shells; II. 8; 1 c? 2 ? 

 juv. Koh Chuen, 30 fath., shell bottom; II; 2c? 1 ? juv., 1$ ovig. Koh Kram, 30 

 fath.; III. 2 and 21; IJ". 



The only adult <? is that from Koh Kram, the only adult ? comes from Koh 

 Chuen. The Ç differs much from the c?, as the surface is very much smoother, 

 the granules are smaller and further apart, so that while the carapace appears 

 rough to the naked eye, the granules do not stand out sharply as in the c?. 



