1870.] 301 [Burgess. 



triangular pad, directed upward, curving over inward and even a 

 little downward, the apex rounded, thickened and gibbous. 



California. 

 Nisoniades Horatius nov. sp. Fig. 13. 



Upper organ : Main body rather long and slender, not high. Pos- 

 terior extremity bearing a greatly elevated crest, similar to that of 

 the following species, N. Virgilius, formed of a half funnel-shaped 

 plate, slender at base, expanding greatly upward, facing backward 

 but scarcely upward, its upper edge recurved and spiculiferous, its 

 right extremity extraordinarily produced, extending as a sort of 

 bristly finger backward and outward, not upward, and at tip curving 

 downward ; its lower edge also sometimes bears a slight bristly tuber- 

 cle in the middle. Hooks much as in N. Virgilius, but the left one 

 almost entirely obsolete; the dependent tooth broad, obpyriform, the 

 edge forming a slightly projecting rim. Arms and inferior armature 

 as in JV. Virgilius. 



It should be mentioned here that the drawing of the upper organ 

 was taken from a larger specimen than that which furnished the illus- 

 tration of the clasps ; the former came from Texas ; the latter from 

 Massachusetts. 



Left clasp: Main body broad and rather short, slightly gibbous, the 

 upper edge full at base, the lower nearly straight. Blade moderately 

 long, the upper three fourths bent over inward so as to be horizontal,' 

 or on the basal half slightly deflected, nearly equal in width, but a 

 little constricted near the middle, the apical fourth tapering to a 

 bluntly rounded apex, which is curved slightly downward; viewed 

 laterally, the blade tapers regularly and slightly, is straight and hor- 

 izontal; viewed from above it curves a very little inward; basal 

 process developed as a slender, scarcely compressed dactyl, bent over 

 backward from its origin, so as to be nearly horizontal on a lateral 

 view, scarcely curving inward, near one third as long as the blade, 

 a little enlarged at the tip, and armed with a few very minute spin- 

 ules around the edge of the enlarged portion. The lobe consists of 

 an upward prolongation of the upper hind angle of the main body 

 into a bluntly pointed triangular expansion, curving inward, leaving 

 the apical border of the main body straight, and at right angles with 

 the lower margin. 



Right clasp : Main body much as on the opposite side, but the up- 

 per portion of the base is not so full, and beyond the middle the upper 

 border is slightly elevated. Blade broad, not very long, directed 



