NO. 1659. AMERICAN SPECIES OF SYNALPHEVS—COVTlEttE. 9I 



width 1 : 4.5 instead of 1 : 5 in xS*. neomeris) , the st5^1ocerite lonijer, and 

 the carpocerite more slender (ratio 1 : 4.4 instead of 1:4). 



Amirante Tshmds, Seychelles Group; Percy Sladen Trust P^x- 

 pedition. 



Type in Paris Museum. 



SYNALPHEUS TRIONYCHIS, new species. 



Very close to S. fossor Paulson, differing in the carpocerite which 

 has the proportion of 1 : 5 instead of 1 : G, in the large cheliped spinous 

 on the palm and the merus, in the small chela less thick than its 

 meropodite, and in the stronger feet of the third pair; in the dactyl of 

 this memher the ventral supernumerary hook is sharp and directed 

 forward, and the dorsal hook is almost as long as the principal hook. 



Saya de Malha, western Indian Ocean; Percy Sladen Trust Expe- 

 dition. 



Type in Paris Museum. 



SYNALPHEUS BAKERI, new species. 



Allied to 8. triunguiculatus Paulson, from which it differs in the 

 rostrum 1.5 times as long as the lateral spines, the carpocerite stout 

 (ratio 1:3.6 instead of 1:4.5), and shorter than the antennal spine, 

 the palm of the large chela unarmed, and the meropodites of the 

 two chelipeds almost unarmed. The dactyl of the third and fourth 

 pairs is much smaller, and the ventral supernumerary hook is not 

 one-third of the principal hook, while it is three-fourths of the same 

 in S. triunguiciAlatiis. 



South Adelaide, South Australia ; M. Baker, collector, for whom it 

 is named. 



Type in Paris Museum. 



SYNALPHEUS PHYSOCHELES, new species. 



Differs from S. triunguiculatus Paulson, especially in the large 

 chela, the palm of which is very swollen and the fingers extremely 

 short (fingers 1, total length 5.33, height 2.2). The fingers of the 

 small chela are contained 3 times in the total length (instead of 

 2.7 times) . The feet of the third pair are more slender, the meropodite 

 being 4 times and the propodite 7 times longer than wide (instead of 

 5.5 and 3.3 times). 



Djibouti, French Somaliland; Ch. Gravier. 



Type in Paris Museum. 



SYNALPHEUS OTIOSUS, new species. 



Differs from S. favaneomeris Coutiere in the shorter carpocerite 

 ratio 1:3 instead of 1:4), in the unarmed meropodite of the large 

 cheliped, that of the third pair stouter (ratio 1 : 3.5 instead of 1:4), 

 the propodite of 5 spines instead of 8, the telson wider at its distal 

 extremity (proj)ortion of the bases 1: 1.5 instead of 1: 1.85). 



Coetivy Island, Seychelles Group ; Percy Sladen Trust Expedition. 



Type in Paris Museum. 



