NEMOGNATHA. 3738 
This genus contains numerous representatives in the New World, the majority of 
which are from the United States, Mexico, or Guatemala, the species becoming fewer in 
number southwards. Some of its members vary greatly in colour, more particularly as 
regards the elytra—from flavous or fulvous to entirely black (WV. lurida, N. nigripes, 
&c.), or with a black vitta (NV. piezata, N. tarasca, &c.); others, WV. cwruleipennis, 
Perty (=versicolor, Chevr.), are equally variable as regards the colour of the head, — 
thorax, and underside. Leconte, in his second Monograph of the North-American 
Nemognathe 1, sinks seven out of the twenty-five described species as varieties. The 
elongated outer lobe of the maxillz is the only character by which this genus can be 
separated from Zonitis, and this character fails in one of the new species here 
described, VV. ephippiata. In a series of eight examples of this insect, six have the 
lobe a little longer than the head, one has it very much abbreviated, and in another 
it is not longer than in typical Zonitis*. In N. cwruleipennis, Perty, it is fully as long 
as the body. 
The Central-American species may be tabulated thus :— 
Head short, very broad, wider than the thorax (still wider in the male); elytra 
violaceous or blue, metallic; upper surface pubescent; outer lobe of the 
maxille as long as the body . . . . . woe ew wt . . Species 1. 
Head short or comparatively short, smaller, not wider than the thorax ; “elytra 
not metallic; outer lobe of the maxille as long as or shorter than the body. 
Hlytra variable in colour—yellow, fulvous, or black, in some species vittate or 
with the base of the same colour as the thorax. 
Thorax subquadrate, with the anterior angles rounded, as long or nearly as 
long as broad; the upper surface pubescent or villose . . . . . Species 2-4, 
Thorax strongly transverse. 
Upper surface finely pubescent . . . . . . . . . . . . . Species 5,6. 
Upper surface villose. . . . - + « Species 7. 
Elytra ochraceous, with black fascie ; the head and prothorax bivittate upper 
surface finely, densely pubescent ee . - « « « Species 8. 
Head more prolonged in front, the mandibles more elongate ; the elytra variable 
in colour, not metallic; the outer lobe of the maxille shorter than the 
body, in some species not longer than the head. 
Thorax rather convex, subquadrate with the anterior angles rounded, or 
subcampanulate. 
Upper surface (the head excepted) glabrous. 
Elytra costate 2. 2. 2. 2... ww we ew ew ee. «Species 9. 
Elytra not costate . 2. . 2. 1. ww ew ee ee ee «Species 10. | 
Upper surface pubescent . ..... . ~ + + « « « « Species 11. 
Thorax campanulate, depressed ; the upper surface pubescent. 
Upper surface yellow. . . . . . . «© 2 ee es ew ee). «Species 12. 
Upper surface black . . 2. 2. 2. 1. 1. ew 1 ew ee we ee «Species 18. 
* Casey, Ann. New York Acad. vi. p. 170 (Nov. 1891), sinks Nemognatha and Gnathium under Zonitis. 
