189 



We know at present that some species of this genus are sedentary animals, living on 

 sponges, corals etc. and that they are not free swimming. This manner of life may probably 

 account for the fact that the great majority of the species collected are only represented by 

 a few specimens and that of several species only one single specimen has been captured. 

 Unfortunately, except for a few species, no information is to be given with regard to the manner 

 of life, so that I am unable to enlarge our knowledge about the biology of the numerous 

 species existing in the Archipelago. The new variety binongcensis of Syn. carinatus (de Man) 

 was collected on a Comatula and the new Syn. triacanthus, a single male of which has been 

 captured at a depth of 112 m., was found living in a specimen of Solenocaulon Gray. 



Several species, especially among the new ones, are perhaps rare forms of a quite local 

 distribution, but, in conclusion, the rarity of specimens of other species may be accidental. 



The genus Synalphms Sp. Bate has been divided by Coutière into six groups that are 

 quite natural and that therefore are also accepted by me. The key to these groups was 

 published in his paper, entitled: "The American Species of snapping shrimps of the genus 

 Synalpkeus, Washington, 1909, p. 3". 



Excepting the Brevicarptis group, all are inhabiting the Indopacific region. 



List of all the Indopacific species of the genus Synalpheus , 

 arranged according to their relationship, as indicated in the keys 1 ). 



I. Comatularum group. 



Comatularum (Hasw.) 1882 = falcatus Sp. Bate 1888. 

 *"amboinae (Zehntner) 1894. 



Stimpsonii (de Man) 1S88. 



Stimpsonii (de Man) var. Maldivensis Cout. 1905. 

 *consobrinus de Man 1909. 



odontophorus de Man 1909. 

 "carinatus (de Man) 1888. 



3; carinatus (de Man) var. binongcensis de Man 1909. 

 ■carinatus (de Man) var. ubianensis de Man 1909. 



Albatrossi Cout. 1909. 



II. Neomeris group. 



*neomeris (de Man) 1897. 



Gravieri Cout. 1905. 

 Tphinoë de Man 1909. 



jedanensis de Man 1909. 

 'miscellaneus de Man 1909. 

 *streptodactylus Cout. 1905. 

 *streptodactyloides de Man 1909. 



modestus de Man 1909. 

 Tococki Cout. 1898. 



Iocasta de Man 1909. 



paraneomeris Cout. 1905. 



"paraneomeris Cout. var. praedabunda de Man 

 *paraneomeris Cout. var. prolatus Cout. 1909. 

 *paraneomeris Cout. var. halmaherensis de Man 



otiosus Cout. 1908. 



1909. 



1909. 



"Charon (Heller) 1S61. 



Helleri de Man 19 10. 

 *Nilandensis Cout. 1905. 



*Nilandensis Cout. var. bandaensis de Man 1909. 

 3; Nilandensis Cout. var. oxyceros Cout. 1905. 



triunguiculatus (Paulson) 1875. 



physocheles Cout. 1908. 



fossor (Paulson) 1S75. 

 *fossor (Paulson) var. propinqua de Man 1909. 



trionyx Cout. 1908. 



Bakeri Cout. 1908. 



Bakeri Cout. var. Stormi n. 1910. 

 'Heroni Cout. 1909. 

 *demani Borr. 1899. 



merospiniger Cout. 1908. 



1) The species collected by the "Siboga" are marked with an asterisk and the new species are printed in a more heavy type. 



57 



SIBOGA-EXrEDITIE XXXIXö'. 25 



