538 MB. W. Y. LANCIIESTEIi OH THE [Dec 3, 



Loc. Kota Bharu, Kelantan. 



A female with ova. The posterior portion of the upper and 

 under surfaces of the carapace are covered by an encrusting 

 Polyzoon, and the tube of a worm is to be seen on the under 

 surface about the level of the chelipedes. 



Dim. 54*5x31*5. 



VII. G-enus Atergatis de Haan. 



8. Atergatis ixteuetuumus Lam. 



Cancer integerrimus, Lam. Hist. An. sans Vert. v. p. 272 (1818). 



Atergatis integerrimug, de Haan, Crust. Japon. p. -4."), pi. xiv. 

 fig. 1 (1839); Alcock, Journ. As. Soc. Bengal, Ixvii. :.', p. 95 

 (1898). 



Loc. Pulau Bidan, Penang. 



Four males and a female. 



The characters given by Major Alcock as distinguishing Ibis 

 species from A. dilatatus de Haan are not entirely satisfactory. 

 I have examined two dried specimens in the Natural History 

 Museum, however, which exhibited this distinction of characters 

 very well, excepting that both species possessed comb-like bristles 

 on the ischia and meri of the legs. Major Alcock's four examples, 

 moreover, of A. dilatatus were quite distinct. But in dealing 

 with the present individuals, although I can unhesitatingly refer 

 them to Lamarck's species, still I find them in some instances 

 presenting characters referred by Major Alcock to A. dilatatus. 

 Of these characters two are very well marked. The one is the 

 presence of the comb-like bristles to which I have referred in the 

 case of the Natural History Museum specimen, which occurs in 

 four out of the five individuals ; the other is the dense hairiness 

 of the outer surface of the third maxillipedes, which is found in two 

 instances, while in two others I should describe this surface as 

 moderately hairy. 



I was able to find only one specimen of A. dilatatus at the 

 Natural History Museum, judging from which I should say that 

 the most marked points of difference between the two species were 

 the much closer pitting of carapace and legs, amounting even to 

 faint rugosity, and the crowded confluent granules ou the sternum 

 in A. dilatatus; the greater relative breadth of the latter may 

 also be taken into account. As regards the greater or less defini- 

 tion of the cardiac region, it may be said that there is a slight 

 variation in this respect in these examples, though in none is the 

 region reallv well defined. 



Dim. d 40x24. 6* 34x20*5. <3 33x20. 6 30-5x18-5. 

 $ 41 x 25. 



9. Atergatis floridus (Ruraph.). 



Cancer floridus Eumph., D'Amboin. Bariteitkamer, p. 10, pi. viii. 

 fig. 5 (1741); de Haan, Crust. Japon. p. 40 (1S39). 



Atergatis floridus, de Man. Merg. Crust, p. 24 ( L888) : id. Zool. 

 Jahrb. Syst. viii. p. 498 (1895). 



