200 A. Alcock — Carcinological Fauna of India. [No. 1, 



122. Pilumnus seminudus, Miers. 



Pilumnus seminudus, Miers, Zool. H. M. S. " Alert " pp. 183 and 222, pi. xxi. 

 fig. C : " Challenger" Brachyura, p. 161 : de Man, Journ. Linn. Soc. Zool. XXII, 

 1887-1888, p. 65. 



" This species resembles P. semilanatus in having the gastric, 

 cardiac, and branchial regions of the carapace smooth and naked ; but 

 it may be at once distinguished by the following characters : — The 

 carapace is broader in proportion to its length, and its anterior parts 

 clothed with a close velvety pubescence, which also extends over the 

 upper and outer surface of the wrist and palm of the chelipeds ; the 

 two posterior teeth of the antero-lateral margins are more distinctly 

 spiniform, the basal antennal joint does not nearly reach to the sub- 

 frontal process ; the granulations of the wrist and palm are much more 

 inconspicuous, those of the outer surface of the palm appear, through 

 the pubescence, to be arranged in four distinct longitudinal series ; 

 the ambulatory legs are slenderer." 



A single small specimen in the Indian Museum, from Mergui, has 

 been referred by Dr. de Man to this species. 



Actumnus, Dana. 



Actwmnus : Dana, Silliman's Amer. Journ. Sci. and Arts, (2) XII. 1851, p. 128 ; 

 and Proc. Acad. Nat. Sci. Philad. VI. 1852, p. 82; and U. S. Expl. Exp. Crust, pt. i. 

 p. 243 : A. Milne Edwards, Nouv. Archiv. du Mus. I. 1865, p. 284. 



Carapace very little broader than long, convex, fairly well or very 

 well areolated : the antero-lateral borders short, cut into teeth ; the 

 postero-lateral longer than the antero-lateral, concave. 



Front from about a third to about two- fifths the greatest breadth 

 of the carapace ; cleft or notched in the middle line, or bilobed with 

 the outer angles independent, usually separated from the supra-orbital 

 angle by a notch or groove. 



Orbits rather large, with one or two notches or fissures or suture- 

 lines (which often, however, are indistinct) in the upper margin, and 

 one (often, also, very indistinct) in the lower margin near the outer 

 angle. The inner lower angle of the orbit is prominent, and often 

 comes so near to the supra-orbital angle as to almost exclude the 

 antennary flagellum from the actual orbital hiatus. 



The basal antennal joint touches or nearly touches the front ; the 

 flagellum which is of moderate length (longer than the major diameter 

 of the orbit) sometimes springs from the orbital hiatus, but is some- 

 times almost excluded from the hiatus. 



The crests of the endostome, defining the expiratory channels, are 



