of the ^^ Genus'''' Peneus. 531 



In other respects it resembles P. sculptilis, Heller^ except 

 in the following particulars : — 



The antero-inferior angles of the carapace are merely 

 rectangular, not dentiform, and the antennular flagella of 

 both sexes are shorter than their peduncle. In these 

 particulars it resembles P. uncta. 



The andricum ends in a pair of large petaloid lobules, the 

 tips of which are incurved, and its basal lateral lobules have 

 the free edge deeply notched. 



The thelycum is a narrow longitudinal plate, laterally 

 constricted or notched near the middle and almost cut in 

 two by a deep longitudinal furrow; it ends posteriorly in a 

 pair of knob- like facets. 



A male and two females from Hongkong, presented by 

 Surgeon-General R. Hungerford. 



In the females the rostrum is like that of many specimens 

 of P. sculptilis, but in the male it is short, barely reaching 

 the end of the second joint of the antennular peduncle, and 

 nearly straight ; it is dangerous, however, to settle the 

 specific form of such a variable structure as the rostrum 

 from an examination of three specimens. 



9. Trachijpeneus asper, sp. n. 



Integument very thick and hard, tomentose, finely 

 scabrous. 



Rostrum quite straight, uptilted, strongly so in the female, 

 not reaching the end of the second joint of the antennular 

 peduncle ; dorsally it is armed with nine or ten teeth (not 

 including the isolated epigastric tooth), which form a crest. 

 Postrostral carina low, broad, and faint, nearly reaching the 

 posterior border of the carapace. An orbital spine. A 

 strong postantennular (antennal) spine, the buttress of 

 which reaches the hepatic fossa. A fine suture runs along 

 the anterior part of the floor of the shallow postantennular 

 sulcus. A similar transverse suture is seen on the branchio- 

 stegite at the level of the third pair of chelipeds. Hepatic 

 spine rather small. Antero-inferior angles of carapace 

 distinctly dentiform. A very indistinct subhepatic groove 

 (the anterior part of the cervical groove) runs from the base 

 of the postantennular buttress to the base of the hepatic 

 siiine; dorsal of the hepatic spine the groove cannot be 

 distinguished. 



On the second abdominal tergum there is a median 

 compressed tubercle. The third to sixth terga are very 



35^ 



