We have shown in the preceding lines that of the 34 old species obtained by this 

 expedition 44% range throughout the whole Indopacific Region but that of the 70 that were 

 not obtained, only 2 viz. A. Seurati and A. paragracilis are as widely distributed. In con- 

 nectión now with the fact that the Indian Archipelago is situated just midway between the 

 western and the eastern parts of the Indopacific Region, we may draw the conclusion that, as 

 a general rule, the range of the remaining 68 species will prove to be rather limited, a con- 

 clusion apparently in harmony with what we know about the distribution of several species 

 described long ago. So e. g. A. socia/is, A. novae-zelandiae, A. brevirostris and A. Halesü 

 are confined to the seas of New Zealand and of South-eastern Australia, while the seas of 

 Japan are inhabited by A. obcso-manus var. japonicus, A. brevicristaitis, A. Haanii, A. japo- 

 niczis, A. malabaricus var. dolichodactylus and A. lobidens. Three species viz. A. architectus, 

 A. EJilersi and A. funafutensis, as also the variety angustidigitus of A. brevirostris (Oliv.), 

 are known to occur in the seas of the Archipelago though not elsewhere and 6 or 7 other ones 

 are probably also confined to these seas. These 19 or 20 species constitute almost one-third of 

 the total number not observed by this expedition, so that we may conclude that the distribution 

 of the numerous species hitherto only observed west of the Archipelago and of the few still 

 only known from Polynesia (A. tryphopus, brevipes, obcso-manus, diadema, pugnax, hoplites and 

 euchiroides) will in general prove to be rather limited and more or less confined to the areae 

 in which they have been diseóvered. Though this conclusion as a general rule may perhaps be 

 regarded as correct, it cannot be denied that in consequence of further research some of these 

 species afterwards will prove to be more widely distributed than is known at present. 



The very natural division of this genus into five groups, the third of which is again 

 subdivided into three subgroups, a division proposed by Professor Coutière in his valuable 

 paper on the Alpheidae of the Maldive and Laccadive Archipelagoes, is also accepted in this 

 work. In the Mcgacheles group, besides 2 known species, 2 new varieties of A. Hailstonei were 

 obtained, which are of some interest because in one of them the dactyli are simple like in the 

 type species, but in the other biunguiculate. 



The remarkable Macrochirus group is represented by 3 known species, by one which is 

 new and by a variety of a Red Sea species (A. gracilis) : the new form closely approaches to 

 A. splendidus Cout. from Djibouti, but it differs by the lateral frontal spines arising from the 

 anterior margin of the front and not from the upper surface of the orbital hoods. It is to this 

 group that has been referred A. acuto-femoratus Dana obtained on the reefs off Sawan, Siau- 

 island and on the west coast of Gebé-island, a rare species with which A. parabrevipes Cout. 

 proved to be identical. 



In the Obcso-manus group, the first subdivision of the group Criuitus, 2 species were 

 obtained which have been diseóvered by the " Challenger" and of each of them a new variety 

 was collected ; the third is A. Lutiui, distributed throughout the whole Indopacific and, finally, 

 South of Saleyer a remarkable form was captured which, probably also belonging to this sub- 

 group, differs from all its species by the dactyli being biunguiculate. The group Crinitus s. s. 

 is represented by 10 species, 4 of which are new and by a new variety of A. Stanleyi. Of 

 these 4 species one is closely related to A. bucephalus Cout. and to A. elypeatus Cout., the 



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