146 Car etiological Fauna of India. 



6. Calappa exanthematosa, Alcock and Anderson. 



Calappa exanthematosa, Alcock and Anderson, Journal Asiatic Soc. Bengal, Vol. 

 LXIII. pt. 2, 1894, p. 177, and Illustrations of the Zoology of the R. I. H. S. ' Investi- 

 gator,' Crustacea, pi. xv. figs., 1, la. 



Extreme length of carapace a little more than two-thirds the 

 extreme breadth. 



The carapace is greatly inflated, especially in the branchial regions : 

 its surface in rather more than its anterior half is covered with large 

 round, or oval, smooth mamillary tubercles having a red base and a 

 shining yellow apex, and exactly resembling smallpox pustules ; and is 

 covered posteriorly with smaller round, or oval, slightly elevated patches, 

 which exactly resemble smallpox papules. The antero-lateral bor- 

 ders of the carapace are quite smooth in their anterior half, and have 4 

 or 5 coarse serrations in their posterior half : the posterior border is 

 beaded, and is bounded on either side by a tooth. 



The clypeiform expansions are little developed, their extreme trans- 

 verse dimension being less than one-third their extreme dimension in an 

 inwardly oblique antero-posterior direction : they consist of about seven 

 serrated teeth. 



The pterygostomian regions have only a few scanty hairs. 

 The front is bifid, the breadth of its tip is half again that of the 

 orbit, beyond which it does not project. 



The flagellum of the antenna is nearly twice the breadth of the 

 oi'bit in length. 



The endostomial septum is narrow, not extending vertically to the 

 level of the mouth, and quite plainly shows its origin out of a fold of 

 the endostome : its anterior border is cut straight, and projects obliquely. 

 The wing-like expansion at the end of the arm has its edge finely 

 serrate and 4- dentate. The upper surface of the wrist and the outer 

 surface of the palm are more or less covered with pustules similar to 

 those on the carapace. The palm has its crest sharply 6- or 7-dentate 

 and its lower surface uniformly covered with beadlike granules. 



The sterna corresponding to the 2nd, 3rd and 4th pairs of legs 

 are much inflated. 



Bay of Bengal, off the Madras coast, 91-112 fms. 



In the young the tubercles on the carapace are sharper, and extend 

 further backwards. 



7. Calappa gallus, (Herbst.) 



Cancer gallus, Herbst, Krabben, III. iii. 46, pi. lviii. fig. 1. 



Calappa gallus, Milne Edwards, Hist. Nat. Crust. II. 105 : De Haan, Faun, 



151 



