56 



TRANS. ST. LOUIS ACAD. SCIENCE. 



blunt-pointed tubercle (Fig. I, d); the other joints almost smooth; 2nd, 

 short, stout, and directed backwards ; 3rd, more slender and as long again 

 as 2nd ; 4th, thrice as long as 3rd ; 5th, as long as 2nd, slender and subfu- 

 siform; labial palpi (Fig. 1, g) moderately covered with hair-like scales, 

 reaching nearly to base of antennae; 3-jointed; basal joint curved and 

 stout; 2nd, half as long and straight; 3rd, short and fusiform : tongue long 

 and smooth. Legs with the usual single spur on the front, a pair on the 

 middle, and two pair on the hind tibia;. Abdomen 0. with the terminal 

 joint laterally compressed, long, horny, bare ; the sheath of the ovipositor 

 acute ; the ovipositor when extended very long, fine, and thread-like ; 6* 

 shorter, blunt, and slightly swollen at tip; the genital hooks large, symme- 

 trical, the upper edge entire and thickened, the lower edge excavated about 

 the middle, with a dark tooth in middle of excavation. 



Approaches in the venation of the wings such genera as Ana- 

 phora Clem, and Amydria Clem., but is at once distinguished 

 from all other known genera by the characters given, and espe- 

 cially by the maxillary palpi. The variation in the wing vena- 

 tion affords another illustration of the unsoundness of the principle 

 of founding genera on the pterogstic characters alone, especially 

 when taken from one or two individuals only. 



Pronuba yuccasella, n. sp. (Fig. 2, c.) 

 Average expanse, $ 1 inch ; o* 0.90 inch. Front -wi?igs, above, uniform- 

 ly silvery-white, the scales loosely set; fringes concolorous : beneath, pale 

 fuscous with a brassy reflection ; paler 

 internally ; fringes either concolorous or 

 paler; costa with a brush of dark hairs. 

 Hind -wings semi-transparent, pale fus- 

 cous both above and below ; paler inter- 

 nally, the fringes white and the brush on 

 shoulder dark. Head white ; antennae 

 and tongue dingy yellow; maxillary pal- 

 pi of same color, with the exception of 

 tentacle, which is darker; labial palpi 

 with scales on 2nd joint dark brown above : eyes black. Thorax white. 

 Legs dingy yellow, more or less covered with pale scales. Abdomen with 

 the terminal joint in $ always bare, with the exception of a few short stiff 

 hairs near tip, and the scales on the other joints very loosely attached. 

 Described from 9 o*s, 15 $s. 



I take the present occasion to describe this new genus, not be- 

 cause it is so characteristic and anomalous, but because, firstly, 

 the species belonging to it has such very interesting habits ; and, 



* Explanation of Fig. 2.— a, larva; b, moth, wings closed; c, same, wings expand- 

 ed—natural size; d, lateral view of a joint; e, head, under side; /, same, upper side; g, h f 

 i,j, k, leg, maxilla, mandible, labium, and antenna of larva— all enlarged. 



