42 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.60. 



anterior corners rounded; margin smooth, wholly without teeth or 

 serration. The lateral margin of second and third keels doubly sin- 

 uous, the median portion bowing out a little convexly. Posterior 

 angles of second and third keels only weakly produced, those of the 

 following keels more distinctly produced, more and more so in going 

 caudad. Margins of keels strongly thickened. Dorsal surface of 

 metazonites in general with three transverse rows of polygonal areas, 

 these well developed entirely across dorsum excepting on second and 

 third plates where they are weaker in the middle region. The areas 

 more elevated on the keels as usual. On the nineteenth tergite the 

 polygonal areas of the caudal row are strongly marked entirely across 

 the width, those of the middle row weaker, while those of the an- 

 terior row are obsolete in the middorsal region. Sides of metazonites 

 granular, the under surface of the keels smooth. 



Anal scale as shown in plate 16, figure 5. 



Gonopods of the male with inner distal branch much more slender 

 than the outer and conspicuously curved. Outer branch flattened, 

 blade-like, distal end obliquely truncate, with acute point at one 

 angle. See further plate 16, figures 6 and 7. 



Length, 50 to 60 mm. ; width 8 mm. in female, 7 mm. in male. 



Locality. — Honduras: La Cciba (type locality), four specimens; 

 Lombardia, one specimen (W. M. Mann). 



Type.—Qfii. No. 844, U.S.N.M. 



103. AMPLINUS ORPHNIUS. new species. 



Plate 16, fig. 8. 



Dorsum black, with the two posterior rows of areas on each meta- 

 zonite a little lighter; black of a somewhat chestnut tinge. Keels 

 yellow excepting at base. Last tergite black across base, elsewhere 

 yellow. Legs and antenna brown. The collum with the usual four 

 transverse series of polygonal areas, of which the anterior and pos- 

 terior series continue across dorsum, while the areas of the two inter- 

 vening series are there obliterated. On the other metazonites there 

 are three transverse rows of stringly differentiated polygonal areas, 

 these being more elevated and pronounced than in the preceding 

 species. On the ninteenth tergite the areas of the anterior series 

 are obliterated, while those of the two posterior ones are conspicu- 

 ously developed, those of the more anterior of these rows being 

 shorter and more tubercle-like. Marginal thickening of keels in 

 general less pronounced than in manni. In the gonopods the outer 

 branch is relatively more slender and less blade-like than in manni 

 and is distally gradually and acutely acuminate. Both branches 

 curve ventrad at distal end (see pi. 16. fig. 8). 



Length, 44 to 60 mm. ; width of male 7.2 mm., of female, 9 mm. 



