9 309 



Persephona elegans (Bell). 



Plate I, fig. 12. 

 Myra elegans Alcock. LXV, 208, 1896. 



Twenty-one specimens of this rare species were taken at nine stations: — 

 West of Koh Kong, 10 — 15 fath.; I. 24; 3 c?. South of Koh Kut, 17—20 fath., 



mud; I. 28; 2 c?. 10-12 miles west of Koh Chang, 20 fath., mud; I. 29; 4 c? 2 ? 



ovig. 20 miles south of Koh Samit, 20 fath.; I. 31 ; 3 c? 1 ? ovig. 4—6 miles south 



of Koh Samit, 14—18 fath.; II. 1; 1? ovig. Koh Kahdat, 5-8 fath., sandy mud; 



II. 16 and III. 4; 1 ? ovig. 7 miles NW. to W. of Koh si Chang, 10 fath., mud; 



II. 24; 1 c?. Between Koh Chuen and Koh Chang, 15 fath., mud; III. 3; 1 c? 1 ? 



ovig. Sound at Koh Chang, 3 — 5 fath., soft clay; 1900; 1 Ç juv. 



Dimensions. — Length of largest c? (Koh Kong), 195 mm., width 105 mm. 



Length of largest Ç (between Koh Chuen and Koh Chang), 183 mm., width 10-4 mm. 



Leucosides longifrons (de Haan). 



Leucosia longifrons Alcock, LXV, 217, 18it(i. 



Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15 — 18; 1 Ç juv. South of Koh 

 Mak, 5—6 fath.; II. 17; 1 ? juv. 



The largest of these specimens is 10-8 mm. long. The front is shorter and 

 more distinctly tridentate than in adults with which they have been compared. 

 The color markings (now very faint) consist of numerous fine brownish wavy lines 

 running inward and backward from the antero-lateral margins, and a few small 

 spots along the lateral margins. 



Leucosides longifrons pulcherrima (Miers). 



Plate I, fig. 14. 

 Leucosia longifrons var. pulcherrima Alcock, LXV, 219, 1896. 



Koh Kahdat, 4—5 fath., sand, stones, coral; II. 15—18; 1 c? 1 ? immature. 



Both have the same color pattern : — two red rings on the posterior half of 

 the carapace, and two larger trefoils of the same color on the anterior half, each 

 enclosing three white spots, two large and one small. 



Leucosides urania (Herbst). 



Plate I, fig. 1. 

 Leucosia urania Alcock, LXV, 220, 1896. 



West coast of Koh Chang, a little north of the small islands, 10 fath., mud 

 bottom, dead shells; I. 16: 1 c?. Koh Lan, 30 fath., mud; II. 3; 1 c? 1?. Koh 

 Kahdat, 5—8 fath., sandy mud; II. 16 and III. 4; 2 c? 1 ?. 



Largest specimen, a male (Koh Kahdat), 303 mm. long, 249 mm. broad. 



These specimens differ from Alcock's description as follows: — The hand is 

 not as broad as long, the dactyli of the legs are a little longer than their propodi; 



I). K. I). Vidensk. Selsk. Skr., 7. Bække, iialurvldensk. o}" niiithem. Aid. V. 4. 40 



