192" J. Wood-Mason— On Telphusidce. [No. 2, 



young of which possess no ciliated buccal lobes, while these are 

 possessed by the allied Littorinid^, and from other instances in 

 which fresh-water allies #f marine animals, which do undergo 

 a metamorphosis, are ametabolous, it is probable that the young of 

 the Telphusidce leave the egg in a condition differing but little 1 

 from that of their parents. 



CRUSTACEA CANCROIDEA. 



TeLPHUSINEA VEL CANCROIDEA 6FRAPSIDICA. 



Fam.—TELPHUSIDJE. 



Genus. — Telphusa, Latreille. 



Diagnosis. — Carapace broader than long,, with the interregional 



furrows little marked, with the exception of the cervical suture 



which is occasionally very deeply impressed. Front deflexed, 



generally with a straight free margin ; orbits large with their infero- 



internal angle sending upwards a stout vertical tooth to about 



against the antenna), which are exceedingly small and lodged in 



the inner canthus of the eye. Antennulary pits pretty long, but 



very narrow. External maxillipecles large with their third joint 



subquadrate, with the antero -internal angle truncated and giving 



insertion to the fourth joint. Sternal region almost as long as broad. 



Abdomen of both males and females constituted by 7 free somites. 



Sub-genus. — Paratelphusa, M.-Edw. 



The species referable to the subgenus Paratelphusa are further 

 characterized by the presence of an acute spine on the superior 

 angle of the meropodites of the chelipedes, situated just behind the 

 constriction near the distal articular end of the joint; the inferior 

 angles of the joint being rounded off, and devoid of the tubercles 

 which are invariably present in Telphusa. 



Paratelphusa Dayana, n. sp. PI. XI. 



The carapace is much broader than long, the greatest breadth 

 being measured between the points of the last epibranchial tooth, 

 extremely convex, ( smooth, punctate, and appears finely granular 

 under an ordinary lens. The branchial lobes are greatly swollen 

 and are not sub-divided into anterior and posterior divisions ; the 

 mesial crescentic portion of the cervical suture is distinctly marked 



