CEUSTACEA. 61 



oblong, and a sharp elongated trigonal claw ; the third tibia subtriangular, the tarsus short, 

 flattened, trigonal, with a falcate claw ; the fifth tibia triangular, very short, flattened ; tarsus 

 transversely ovate, with a small narrow claw. 



Abdomen (of male) seven-jointed, the joints from the first to the sixth nearly of the same 

 width as in Notopus, the last joint trigonal. 



Hab. Borneo (Unsang). 



Cosmonotus differs from Notopus, De Haan, in wanting the post-frontal, elevated denti- 

 culated ridge; in the dorsal keel ending abruptly in front, instead of terminating in a 

 central frontal spine ; in the front being notched, with a single spine on each side ; in the 

 carapace being much compressed, more especially in front, and in the produced and angular 

 form, while in Notopus it is almost straight across the front ; and in the sides being entire, 

 with a short sharp spine at the antero-lateral angle. The species is named in compliment to 

 J. E. Gray, Esq., F.R.S., Keeper of the Zoological department in the British Museum. 



xii. pentEid^:. 



A new species of Sicyonia, Edwards, of a scarlet colour, finely variegated with orange 

 and yellow, with a greyish pubescence on the dorsal surface near the crest, was obtained in 

 the Sooloo Sea together with a few Zocsce. The Stenopus, Sicyonia, and Penmcs, usually 

 swim in a slow and deliberate manner forwards, and occasionally with a sudden jerk propel 

 themselves backwards. They keep at a considerable distance from the shore and seem 

 to love deep still water, never appearing when the surface of the sea is ruffled. 



1. STENOPUS, Latreille. 



1. STENOPUS HISPIDUS, Latreille. (Tab. XII. Fig. 6.) 



Tho-race spinis multis parvis pilisque sparsis obsito. 



Fronte acuminata gracili sursum directa, non ultra articulum basali antennarum superiomm pertinente ; 

 antennis perlongis filiformibus. 



C/ielis brevioribus quam paria pedum secunda, longe ultra appendiceal lamellarem antennarum infe- 

 riorum porrectis. Pari tertio pedum longiore quam totum corpus multis seriebus longitudinalibus dentinm 

 aeutarum, tarsis duorum parium ultimorum pedum bifidis. 



Abdomine lamina media pinnse caudalis in centre- sulcato, supra seriebus duabus spinarum. 



Hab. Insulas Philippinas. 



Stenopus Mspidus, Latr. E. A. vol. iv. p. 93. Cuv. E. N. (Croch), t. 50. f. 2. Edw. Crust, vol. ii. 

 p. 407. t. 25. f. 1. Palamon Aispidus, Oliv. Enc. vol. viii. p. 666. Seba, vol. iii. t. 21. f. 617. 



Carapace covered with numerous small spines and scattered hairs. 

 Front pointed, slender, elevated, not extending beyond the basal joint of the upper 

 antennae ; antenna? very long and filiform. 



R 



