728 PROCEEDINGS OF THE NATIONAL MUSEUM. 



Strongly inflated; all thejoints more or h^ss tuberculate on the ventral 

 face and beset with bristles on the apical Joints. 



First six pairs of male legs with a fleshy sole at apex of the last joint, 

 the claw shortened. 



First pair of leys <tf male six-jointed like the others; the coxa' long, 

 approximate. 



Second pair of male legs with the coxa* produced ventrad into a large 

 process, in the dei)ression of the flattened ventro-posterior face of which 

 is the seminal opening, 



Male genitalia with basal joint very small, flattened; distal joint very 

 large, laterally compressed, tricarinate; ungual i)ortlon very long, 

 com])licate, thin and com])ressed at base to form a flexible ])seudo- 

 articulation, above which it is inflated, then extended into a long flex- 

 uous flagellum, very slender distally. 



ANALYTICAL KKY TO TUK SPECIES OF ASTROUE8MUS. 



Body larj^o aud robust (65 ram. by 13.5 mm.); dorsum strongly convex, distinctly 

 ruga lose to tlie naked eye, cs])ecially on the carinir; marginal calli prominent and 

 broad, that of the fifth segment strongly arcuate mesad, being greatly widened to 

 accommodate the large poriferous cavity: A. taiu/a, p. 736. 



Body much smaller or smooth and shining; marginal calli modcralcly developed, 

 the poriferous merely oviil, those of the fifth i\ot so ditferenf from those of the sev- 

 enth segment 



Body rather snnill and slender (33 nmi. by 6.5 mm.); antennas and legs slender, 

 eciual in length to the width of the body; transverse ridges of sterna slightly devel- 

 oped; process of sternum of segment 15 A'ery small, tuberculoid: A. petilii8,-p. 733. 



Body larger and more robust; anteunic iind legs more robust, not equaling in 

 length the diiimotor of the body; transverse ridges of sterna distinct; process of 

 segment 15 large iind strongly chitiui/ed 



Process of sternum of segment 6 sulxjnadrate, the sides being snbparallel and the 

 distal margin nearly transverse, except for a suuill median apiculus; two distinct, 

 flattened processes between the bases of posterior ))air of legs of segment 8: A. liiri- 

 diiii, p. 734. 



Process of sternum either subtriangnlar or narrower near the base than farther 

 up, and with a large median projection, so that there is no transverse distal margin; 

 segment 8 with the ridges of the sternum scarcely larger than the others 



Body very rolmst (.55 ram. by 14.5 mm.); the dorsum but slightly convc^x; the 

 cariuic broad aud fitting closely together: ^1. robiistus, p. 731. 



Body not more than 13 mm. in diameter by the above length ; dorsum mure convex, 

 the carina' distinctly sei)arated 



Copnlatory legs slightly or not at all expanded, or at least entirely unarmed 

 immediately below tlu^ slender terminal sj)ine: J. la.nifi, ]>. 731. 



Copnlatory legs distinctly and abruptly flattened and expanded below the ter- 

 minal spine; lu-oximal corner of expanded i)ortion ])roduced into a distinct, recnrvcsd 

 spine 



.Size about 45 mm. by 11.5 mm. ; dorsum distinctly rugulose striate longitudinally; 

 expanded subtermiual portion of copnlatory legs sluu't, the proximal spine short: 

 J. striafuH, p. 733. 



Size at le.ast 55 ram. by 12.5 nun. ; dorsum not rngnlose longitudinally, appearing 

 smooth to the naked eye; expanded subtermiual ])orti(m of copnlatory legs longer 

 and thinner, the proximal spine longer (see Plate LX, tig. Ic) : A. skllifer, p. 729. 



