27 



Blightly upward, especially at the tip, slightly excised along the mid- 

 dle, a very little larger at the apex than at the base, gibbous at the 

 base, beyond flat, twisted so that the outer surface becomes nearly 

 horizontal, curved slightly inward, the apex, especially the upper 

 angle, still more so, the tip docked almost squarely and a little diag- 

 onally, so that the apical edge is directed almost straight backward, 

 very broadly rounded, the edge slightly thickened, the angles not 

 sharp; basal process consisting of a small, backward directed, tri- 

 angular tooth, bluntly pointed and as long as the smallest breadth of 

 the blade, and a little longer than the breadth of its own base. Lobe 

 consisting of an upward, posterior projection of the upper hind angles 

 of the main body, forming a subtriangular, broadly rounded, gibbous 

 pad, curving inward and a little backward, separated from the basal 

 process of the blade by a very broad, deep and regularly curved 

 excision. 



New England, Texas. 

 Nisoniades Virgilius nov. sp. Fig. 14. 



Upper organ ^- Main body long and slender, not high. Posterior 

 extremity bearing greatly elevated asymmetrical alations, united in a 

 somewhat horseshoe-shaped, curving, hollowed plate or crest, exces- 

 sively produced as a slightly upraised, pointed triangle on the right 

 side, directed backward and upward; the whole crest faces upward 

 and backward, its united upper edge fringed with minute spicules, 

 and is supported on either side by a slender ridge running from near 

 its middle a short distance forward to the side of the main body. 

 Hooks very small, asymmetrical, the right being much the larger, 

 pointed, scarcely curving downward at tip, approximate at base, 

 divergent; tooth small, sessile, spatulate, appressed. Arms asym- 

 metrical, very slender, nearly uniform, curving, having first a gen- 

 eral direction downward and slightly forward, afterwards backward, 

 upward and inward, the curve quite regular, expanding slightly at 

 tip and bearing between the extremities the inferior armature — a 

 rather small rounded field of minute raised points. 



Left clasp; Main body almost identical in form with that 

 of iV. Iloratlus, excepting that the apical border lies at a 

 little more than a right angle with the lower margin, on 

 account of the greater projection of the lobe. Blade as in 

 N. Horaiius, excepting that the basal half of the upper two thirds 

 is bent over horizontally, the part beyond not quite so much ; it is 

 also a httle broader, directed slightly upward, the tip bent scarcely 



