21 321 



Gonatonotus pentagonus White. 



Gonatonotus pentagonus White, Proc. Zool. Soc. London, XV, 58, 1847; Adams andWniTK, Zool. Saraaiang, 

 Crust., .■ÎS, pi. VI, fig. 7, 1848. 



Between Koh Kut and Koh Kahdat, 10 fath., shell bottom; I. W\ ICI juv. 

 Koh Chuen, 30 falh., shell bollom; H ; 5 cJ* 3 ? (2 ovig.) 5 juv. Koh Kahdat, 5—8 

 fath., sandy mud; II. 16 and III. 4; 1 Ç ovig. Between Koh Rin and Cliff Rock 

 (N. of Koh Kram), 15 fath.; III. 2; le? 1? 1 juv. Koh Kram, 30 fath.; III. 2 and 

 21; 2 c? 3? (2 ovig.) 5 juv. On Plococidaris bispinosa (Lamk.), off Koh Kram, 30 

 fath., stones, shells; II. 23; le? 1 ? ovig. 2 juv. Koh Kahdat, 8 — 10 fath., mud; 



I. 27; 1 juv. Koh Chuen, 30 fath., shell bottom; I. 2; 5 juv. 



Subfamily Eumedoninæ. 

 Zebrida adamsii White. 



Zebrida adamsii White, Proc. Zool. Soc. London, XV, 121, 1847 ; Adams and White, Crust. Zool. Samarang, 

 24, pi. VII, fig. 1, 1848. 



On Salmacis bicolor Ag., off Koh Kram, 30 fath., stones, shells; II. 23; 1 Ç. 

 Between Koh Mesan and Cap Liant, 5—9 falh.; II. 4—7 ; 1Ç ovig. On Toxopneustes 

 pileolus (Lamk.), north side of Koh Mesan, 10-15 fath.; II. 5; 2 J". Koh Chuen, 

 30 fath., shell bottom; I. 2; 1 ? juv. Koh Kram, 30 fath. ; III. 2 and 21 ; 1 c? juv. 1 juv. 



The young specimens have the legs proportionally longer and narrower, and 

 the projections small and inconspicuous. The smallest individual, 2 mm. long, has 

 short blunt frontal lobes, the tip only of the lateral lobe is directed forward, the 

 chelipeds and legs are unarmed, the latter slender, the propodus of the last pair 

 only having a feeble projecting point on its posterior edge. 



This is the crab mentioned by Dr. Mortensen in his work on the Siani- 

 Echinoidea I. (Zool. Res. Danish Exped. to Siam 1899—1900. II. Mém. Acad. R. d. 

 Sei. Copenhague. 7. sér. I. 1904 p. 66 and 120) which was found on Salmacis bicolor, 

 var. rarispinus Ag. and Toxopneustes pileolus (Lamk.), devouring "the spines (pro 

 bably the muscles only), pedicellariæ and tube feet, quite cleaning the test; it 

 mostly follows one area from the top downwards." 



Superfamily Brachyrhyncha or Cancridea. 

 Family Ocypodidæ. 



Subfamily Ocypodinæ. 

 Ocypode ceratophthalma (Pallas). 



Ocypoda ceratophthalma Alcock, LXIX, 345, 1900. 



Coast of Koh Mak, sandy shore; I. 9; 4 juv. Coast at north point of Koh 

 Chang; I. 15; 1 juv. West coast of Koh Chang; I. 16; 2 juv. Coast of Koh Mesan; 



II. 4-5; 1 juv. Koh Pløt; II. 10; 3 juv. Koh Kahdat; II. 18; Id". 



