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this species from Cheval Paar, Ceylon, which record, indeed, should be very interesting, but I am 

 not quite sure whether his species should not belong to Ath. Naifaroensis or AtJi. aretcformis. 

 Ath. veloculus Sp. Bate, collected by the "Challenger" also at the Cape Verde Islands, is 

 considered by Coutière as a variety of Aih. nitescens. The other atlantic species is Ath. 

 Grimaldii Cout., a form inhabiting the same Archipelago and observed also at Belle-Isle; 

 this species, described quite lately, is remarkable by the extraordinary development of the 

 Appendix masculina on the 2 nd pleopods of the male. Ath. Naifaroensis Cout., of which only 

 the female is known, inhabits the Maldive Archipelago ; in this species the supra-corneal tooth 

 is more strongly developed than in the two european species and the carpus of the first 

 pair of legs is shorter, when compared with the merus. Closely related to this species is Ath. 

 areteformis Cout. from the same Archipelago, which chiefly differs by the absence of the infra- 

 corneal spine. The fourth species of this group is Ath. Granti Cout. from the South Adelaide 

 coast, which differs from the preceding by the lack of a supra-corneal tooth and especially by 

 the dactyli of the three posterior legs being distinctly biunguiculate. 



To the other group belongs in the first place Ath. dimorphus Ortm., which has given 

 its name to the group. This species inhabits the Red Sea (Suez) and has also been observed 

 at Perim, Djibouti, Dar-es-Salaam, even at the shores of New Caledonia and perhaps at those 

 of the Fiji Islands. A variety monoceros Heller occurs in the Red Sea. Ath. Minikoensis Cout., 

 of which only the female was hitherto known, differs from Ath. dimorphus by the carpus of the 

 first pair of legs being much shorter than the merus and than the chela : this species occurs at 

 Minikoi Atoll and was captured by the Siboga Expedition near the island of Siau and on the 

 west coast of New Guinea. The third, Ath. Haswelli Cout., from the South Adelaide coast, 

 is closely related to Ath. Minikoensis, but the carpus of the first pair of legs of the female (the 

 male is unknown) is slender as in Ath. dimorphus. Ath. orientalis Pearson is also only known 

 by the female, at least as regards the first pair of legs, and it inhabits the shores of Ceylon ; 

 this species is also closely related to Ath. Minikoensis, but the carpus of the first pair of legs 

 is not conicak but has a more slender form, being almost 5-times as long as thick at the distal 

 extremity. The fifth species is Ath. Djiboutensis Cout., that occurs at Djibouti, in the Maldive 

 Archipelago, at Minikoi Island and even in the Pacific, at the shores of the island of Funafuti. 



Besides Ath. Minikoensis Cout., four species were collected in the East Indian Archipelago 

 by the Siboga Expedition that all proved to be new to science. Ath. parvus, from the south 

 coast of Timor, is only known by the female-, it belongs to the Nitescens group. By the 

 biunguiculate dactyli of the three posterior legs and by the lack of a supra-corneal tooth it 

 much approaches to Ath. Granti, but, while in the latter the legs of the first pair resemble 

 those of Ath. Naifaroensis, in those of Ath. parvus the carpus appears 2, 5-times as long as 

 thick and the chela is hardly longer than the merus. Two species of the Dimorphus group were 

 collected, that differ from all the other known species of this group by the dactyli of the three 

 posterior legs being biunguiculate. In Ath. jedanensis from the Jedan Islands the legs of the 

 first pair of the male resemble those of Ath. Djiboutensis, while those of the female are equal 

 and much agree with those of Ath. Minikoensis. The other, Ath. Sibogae, collected at various 

 localities of the Archipelago, has the first pair of legs much as in Ath. Djiboutensis. 



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