39 



is broad and extends almost to the apex of the Uncus. The distal 

 portions of the Clasp (PI. V, Fig. 4) are noticeably different to those 

 of any of the preceding forms ; the Blade is long drawn out, evenly 

 and very bluntly rounded, not hooked or pointed, the outer and dorsal 

 margins are irregularly dentate and the dorsal margin rises obliquely 

 into the Proharpe, without any definite point of demarcation between 

 the two portions ; the Proharpe lies in the same plane with the whole 

 clasp, is very broad basally, bluntly rounded apically and irregularly 

 and prominently toothed. The Lobe is much shorter than the Blade 

 and its rounded outer margin is entirely covered by the proharpe. The 

 Penis (PI. VI, Fig. 7) is straight, slightly enlarged apically and with 

 a single asymetrical lateral tooth shortly below the apex. 



9 . The \^aginal Plate (PI. VI, Fig. 5) is very characteristic; the 

 Lateral fold is spirally bent, giving the impression of an upper and 

 lower portion, connected by a thin rod of chitin; the area around the 

 vaginal opening shows comparatively simple structure, the chitinous 

 fold on each side resembling a bird's wing on the flight; the Alae are 

 highly chitinized, sharply pointed apically, the two sides diverging 

 rapidly and broadly towards the base. 



Concerning the habits of this species Oslar's article (Ent. News, 

 XI, 495) affords us some very interesting information; according to 

 Oslar the $ is diurnal, flying very rapidly in the hottest sunshine; 

 the 9 , however, is largely nocturnal, and oviposition occurs from 

 sunset until well into the night. The food plant is Yucca, but of the 

 early stages we know nothing. 



Habitat. Arizona ( ?) ; S. W. Colorado (near Durango) (May- 

 June) (Oslar) ; New Mexico, (Highrolls, Ft. Wingate) (June). 



(2) M. STRECKERi TEXANA n. subsp. (PI. II, Fig. 9 9.) 



M. cofaqui *Strecker (non Strecker, 1876), Brook. Bull. III. 66 (1880'); French, 

 Butt. East U. S. p. 386 (1885) (partim) ; *Coi-nstock, Man. Study Ins. 

 367, Fig. 448 (189s) ; Dyar, Jour. N. Y. Ent. Soc. XIII, 141 (1905). 



E.xcept for its rather smaller size this subspecies bears somewhat the same 

 relation to streckeri streckeri that yuccae yuccae does to yuccae coloradensis; 

 the yellow of the maculation is deeper in tone, approaching orange-yellow rather 

 than the pale lemon-yellow of streckeri streckeri; $ above as in the type form, 

 the hair of secondaries slightly longer and thicker ; primaries beneath with the 

 yellow spots as large as above and well defined ; secondaries with the sub- 

 marginal band of spots lacking ; a small creamy spot below costal margin near 

 junction of subcostal and radius, a still smaller spot in cell just before the in- 

 ception of vein M:, and a faint pale scaling near anal angle; the dark blotches 



