characters of this species are intermediate between those of these two Alphei. Two other species 

 closely approach to A. styliceps which also inhabits the Maldive and Laccadive Archipelagoes 

 and the fourth is a form of small size allied to A. lo7igecarinatus. Three species known already 

 long ago and 5 new ones are representing the subgroup Insignis Cout., that connects the 

 Crinihis and Brevirostris groups with one another. The new A. praedator is interesting, as it 

 bears, just as A. didcus, at each side of the rostral carina, a pointed tooth and A. bicostatus, 

 which is related to A. cristatus from Torres Straits, is also a remarkable form. A. Philodetes 

 is another new species apparently alHed to A. Lancclotl, but its true position is doubtful, 

 because the larger cheliped is missing in the single specimen. Two new species, A. teniiicarpits 

 and A. teimipes^ as also an unnamed form, are characterized by their three posterior legs 

 being very slender. 



No less than 10 species of the Brevirostris group, 6 of which are new to science, were 

 collected by this expedition. One of the old species is the well-known A. rapax Fabr., two adult 

 specimens of which were captured off Nusa-Laut-Island : this species probably ranges throughout 

 the whole Indian Ocean. At a much greater depth than the other species an egg-bearino- 

 female was captured, which with some doubt is referred to A. macroscehs. Different from the 

 latter, in almost all the new species of this group the rostral carina is more or less prominent 

 and continued to the middle or even beyond the middle of the carapace ; the new A. acnto- 

 carinatiis approaches to A. inacroscclcs by the slender form of the thoracic legs. 



The Edzoardsi group, finally, the largest of all, is represented by 17 species, 4 of 

 which are new, by 4 new varieties and by a species that did not yet receive a specific name. 

 The new A. proseuchirus agrees with A. dis-incistis by the flattened form of the rostrum, 

 but it differs by the larger chela being hardly emarginate on the lower border and by the 

 very slender shape of the three posterior legs. A. Coiiticrci is chiefly characterized by the 

 prominent rostral carina, continued beyond the posterior third of the carapace. About the very 

 remarkable A. Polyxo, the dactyli of which are biunguiculate, I must observe that its place 

 in this group remained doubtful because, unfortunately, in both specimens the larger cheliped 

 is wanting. The new variety iniifafrix of A. paretichirtis is noteworthy because the dactylus of 

 the smaller chela presents the Balaeniceps-form not only in the male but also in the female, 

 imitating^ as regards this character, the long-known A. strenuzis. 



Several new species are only represented by one, two or three specimens, a fact perhaps 

 fortuitous, perhaps due either to the rarity of these species or to their manner of life : we know 

 indeed through the observations of Coutiere, that some species are living in sponges or between 

 the corals of the reefs, in deep holes bored by mollusks or under stones. 



As regards the bathymetrical distribution we must in the first place draw the attention 

 to the fact that of more than one-third of the species, exclusive of course of the new forms 

 collected by this expedition, nothing is known about the depth at which they have been 

 obtained. As a general rule the species of this genus are living in shallow water, for more 

 than half the number of all the indopacific species of AlpJieus, inclusive those obtained by 

 this expedition, have been observed at depths not greater than 30 fathoms or 54 meters; some 

 of these species, namely those that were captured in the Maldive and Laccadive Archipelagoes 



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