ART. 8. MILLIPEDS OF CENTRAL AMERICA CHAMBERLIN. 45 



terior corner of the keel is rounded, the posterior one more narrowly 

 so, a little obtuse. In the third and fourth keels the posterior angle 

 is more obtuse. On the keels from the second to the fourth there is 

 a slight lateral tooth at the anterior corner. The keels of the middle 

 and posterior regions of the body in particular are very narrow. In 

 the nonpore-bearing keels both corners are rounded and the margins 

 are bent up uniformly all around excepting a slight raised angle or 

 tubercle at the caudal corner; both anterior and posterior margins 

 convex. The porigerous keels are similar with the addition of the 

 sharply set-off, protruding, pore-bearing process, which is in cross 

 section a little elliptic and projects laterad from the margin. Anter- 

 iorly the pore body is near the middle of the side, but shifts farther 

 and farther back in going caudad and is at the caudal corner on 

 the seventeenth segment, though projecting only slightly caudad. 

 Only on the eighteenth and nineteenth keels are the posterior angles 

 produced, but the processes are slight. In these most posterior keels 

 the pore swelling is less sharply set off and does not project out 

 laterad (see further pi. 16, figs. 10, 11, and 12) . 



Anal scale as shown in plate 16, figure 13. 



Length, about 32 mm. ; width, 4.5 mm. 



Locality. — Costa Rica : Port Limon, one female (W. M. Wheeler, 

 November, 1911). 



Type.— C^i. No. 5022, M.C.Z. 



While only the female of this species was secured, the form of the 

 keels is so characteristic that there will probably be no difficulty in 

 its recognition. 



113. CHONDRODESMUS TUBERCULIFER, new species. 



Plate 17, figs. 1-6. 



Chocolate brown above, the prozonites sometimes black, with outer 

 portion of keels yellow. Legs and antennae fulvous, the former 

 sometimes in part tinged with brown. Anterior and lateral margins 

 of collum forming an even and broadly convex curve. Caudal mar- 

 gin arcuate, a little concave toward each end, so that the caudolateral 

 angles are a little acute, not at all rounded. First, second, and third 

 keels as broad as the fourth and fifth. Anterior corners of the keels 

 rounded, and on the first ones with a small tooth at the lateral edge. 

 Caudal corners of second to fourth keels rectangular (pi. 17, fig. 1). 

 On the porigerous keels the caudal corner appears to be angularly 

 excised behind the pore swelling, the outer edge of the posterior ex- 

 pansion beginning at caudal edge of swelling (pi. 17, fig. 2). On 

 the fifteenth keels the angle of posterior margin extends caudad the 

 same distance as the outer process, but on the sixteenth the latter 



