285 



Lateral spine of the basicerite as long or slightly longer than the stylocerite, upper spine as 

 in Syn. qiiadrispinosns. 



Posterior margin of 6'^ abdominal somite armed with four triangular, subacute 

 teeth, one at each outer angle and one at either side of the middle, the external teeth twice 

 as long as the submedian teeth. Telson 2,8-times as long and twice as wide at the base as 

 the posterior margin is broad, the latter being a little wider, comparatively, than in Syn. qjiac/ri- 

 spiiios2is\ posterior margin as in this species. As regards the arrangement of the spinules of 

 the upper surface that are 0,175 mm. long, one-eighth or one-ninth of the length of the telson, 

 this species accords with Syn. quadrispinosus : the proportion between the length of the telson 

 and the distance of the anterior pair from the posterior margin is 1,35, the proportion between 

 the distances of either pair from the posterior margin 1,4. 



Merus of small cheliped 2,65-times longer than wide, upper margin unarmed at ape.\. 

 Relative dimensions of the small chela: fingers i; total length 3; height 1,2; this chela is just 

 2,5-times longer than high and has therefore a much stouter form than that of Syn. qjiadri- 

 spinostis. Fingers as in this species. Merus of second legs 4-times as long as wide, the following 

 joints are missing. 



Relative dimensions of third legs: merus 2,71; carpus i; propodus 1,77, numbers agreeing 

 with those of Syn. quadrispmosus. Merus 1,53-times longer than the propodus. Merus 3,05-times, 

 propodus 4,2-times longer than wide, both members being of a stouter shape than in Syn. 

 qiiadrispinosns \ the propodus with eight spinules, long 0,09 — 0,1 mm. Dactyl us measuring a 

 little more than one-sixth the propodus and twice as long as broad near the articulation ; its 

 shape is the same as in Syn. quadrispinosus. 



Ova large, 1,3 mm. long. 



Length i 2 mm. 



136. Synalphens qnadrispinosns de Man. 



J. G. DE M.VN, in: Tijdschr. d. Ned. Dierk. Vereen. (2) Dl. XI, 1910, p. 29S. 



Stat. 49'. April 14. 8° 23^5 S., II9°4'.6E. Sapeh-Strait. 70 m. Coral and shells, i young male. 

 Stat. 164. August. 20. i°42'.5 S., I30°47'.S E. Between Misool and New-Guinea. 32 m. Sand, 



small stones and shells, i adult specimen without eggs. 

 Stat. 273. December 23/26. Anchorage off Pulu Jedan, East coast of Aru-islands (Pearl-banks). 



13 m. Sand and shells, i adult ova-bearing female. 

 Stat. 310. February 12. 8° 30' S., ii9°7'.5E. Sapeh Strait. Ji m. Sand with few pieces of 



dead coral, i ova-bearing female. 

 Stat. 315. February 17/18. Anchorage East of Sailus Besar, Paternoster-islands. Depth up to 



36 m. Coral and Lithothamnion. i young male. 



A remarkable new species of the Biunguiculatus group, distinguished, like Syn. quadridens, 

 by the armature of the 6''> abdominal somite. • 



Frontal and antennal region in the adult female from Stat. 273, which is considered as 

 the t)-pe, much resembling those of Syn. biunguiculatus (Stimps.) Cout. (vide: H. Coutiere, 

 Alpheidae Maid, and Laccad. Archip. 1905, PL LXXI, Fig. 8). Rostrum short, subacute, about 

 3-times as long as wide in the middle, its upper margin obtuse and appearing, in a lateral 



153 



SIliOGA-EXPEDITIE XXXIXfl'. 3y 



