No. 1810. DESCRIPTIONS OF NEW MILLIPEDS—COOK. 165 



Posterior segments but little shorter than the others, gradually 

 narrowed and somewhat compressed; constriction and punctations 

 slight. 



Last segment abruptly narrowed and distinctly angled at the apex, 

 equaling the anal valves or very slightly produced. 



Anal valves strongly convex, with rather thin, distinctly com- 

 pressed slightly prominent margins, bordered by shallow grooves. 



Preanal scale small, the posterior margin nearly transverse. 



Males with anterior legs rather strongly crassate, all of the joints but 

 the last swollen on the under side into rounded prominences. Claws 

 not enlarged. 



Coxa? of third and fourth pairs of legs of male produced into very 

 small papilliform processes, turned obliquely forward. 



Coxa? of fifth pair of male legs with processes four or five times as 

 long as the others and thick in proportion, about twice as long as 

 broad, subcylindric, slightly tapering, with the ends abruptly hooked 

 forward. 



Coxa? of sixth and seventh pairs without processes, merely rounded 

 like the other joints. 



Coleopods with ventral plate forming a large, oblong-ligulate median 

 process nearly twice as long as broad, emarginate at apex. Anterior 

 lobes widely separated, stout columnar, the outer margins nearly 

 straight, the rounded apex slightly incurbed. Posterior lobes small, 

 with simple incurved apices only slightly exceeding the corners of the 

 ventral plate. 



Gonopods not exposed; doubtless retracted into the unusually thick 

 bulbous bases of the coleopods. 



Sixth and seventh segments of males notably broader, the seventh 

 inflated and prominent below; coalesced pleura? of seventh segment 

 with a very broad transversely striate anterior slope, the median 

 suture obsolete. The dorsal part of the seventh segment very short, 

 that of the sixth segment unusually long. 



The affinity of this genus with Anelus is certainly not close, and 

 may prove to be very remote, but the external similarities are at least 

 interesting. The transverse row of punctations renders the segments 

 much alike, and the apex of the last segment shows a slight projection, 

 giving at least an external appearance more similar to Anelus than 

 any other Mexican or Central American type available for comparison. 

 Both genera may prove to be relatives of Trigoniulus, and may assist 

 in determining whether that cosmopolitan genus is of American or 

 Old World origin. 



GLOSSELUS MUSARUM, new species. 



Type. — Cat. No. 799, U. S. National Museum, collected in a banana 

 plantation at La Colombiana, Costa Rica, April, 1903, by O. F. 

 Cook. 



