402 CEYLON PEARL OYSTER REPORT. 



Xantho (Leptodius) exaratus (H. M.-Edw., 1834) A.3, p. 118. 



Locality : Trincomalee, one specimen (female, doubtfully adult). 



Description : It answers to Alcock's description. Comparing with Kossmann's 

 figures, its greatest carapace-breadth is across the region of the 3rd, not the 4th. 

 Literal teeth. 



Cycloxanthops [= Cycloxanthus] lineatus, A. M.-Edw., 1867 A.3, p. 124. 



Localities : Coral reef, Gulf of Manaar, three specimens (a, b, c) ; ( Iheval Paar, 

 one specimen (d) ; off Kaltura, one specimen (e). 



Description : All are males, apparently adult. The spirit has removed the colour, 

 but the specimens give evidence (under lens) that there are colour varieties within 

 the species. 



A. In specimens (6) and (d) there are faint whitish lines on the carapace in the 

 positions represented in A. Milne-Edwards' figure. 



B. In specimens (a) and (e) the carapace is covered with large spots a little darker 

 than the general surface, each of which is surrounded by a whitish ring. 



C. Specimen (c) has neither lines nor spots. 



Polycremnus ochtodes (Herbst, 1783) A.3, p. 135. 



Localities: Pearl banks, six specimens (three <?, probably adult, two ?, one 

 young ?); coral reefs, Gulf of Manaar, three specimens (two 6*, probably adult, and 

 one ? , probably adult). 



Actaea speciosa (Dana, 1852) A.3, p. 143. 



Locality : Gulf of Manaar, one specimen. 



Description: Female, adult, but non-ovigerous. C.L = 6*25. It agrees with 

 Kossmann's description and photograph of Psaumis glabra. It also agrees with 

 Dana's description, but differs from his figure in some points. In mine (1) the lobe 

 2M is more deeply subdivided ; (2) though in the posterior portion of the carapace 

 the grooves are very shallow and partly obliterated by granules, it is still possible to 

 distinguish, somewhat indefinitely, the lobes 1R, 2R, IP and 2P. There is a distinct 

 fissure between the outer angle of the orbit and the sub-orbital border, stated by 

 Alcock to be absent in his specimens (three, from the Persian Gulf, Ceylon, and 

 Andamans). de Man finds this fissure in his specimen (' Abh. Senckb. Ges.,' xxv., G09). 



Differences between my specimen of A. speciosa and the descriptions of the closely 

 allied A. rufopunctata are that in the former: (1) Carapace is relatively longer and 

 narrower ; (2) carapace, chelipeds, and walking legs devoid of hair ; (3) lobulation of 

 carapace much less complete and bold except on antero-lateral regions, that of chelipeds 

 and walking legs is much as in A. rufopunctata ; (4) the anterior tongue of 3M 

 reaches farther forward ; (5) the longitudinal division of 2M is hardly complete 

 posteriorly ; (P>) the groove separating 2M from 2L diverges a good deal anteriorly 



