M 



IE WEST AMERICAN SCIENTIST 



Volume VIII. AUGUST, 1893. Whole No. 66. 





SOME L,ARV,E ON SCRUB OAK. 







By C. H. Tyler Townsend. 



The following five species of lepidopterous larvae were either 

 taken directly from, or believed to have come from, the scrub 

 oak which grows in the Organ mountains, in southern New 

 Mexico. This scrub oak has been determined for me by Mr. 

 Walter H. Evans as quercus undulata var. wrightii. 



(Figures in parentheses refer to numbers of alcoholic speci- 

 mens in New Mexico College collection). 



(a) A LIGHT GREEN GEOMETRID LARVA OR SPAN-WORM. 



Two pairs of prolegs, one on anal (13th) segment, and the other 

 evidently on hindmost edge of segment 10, but appearing to be 

 on 11. Body elongate and narrow, subcylindrical. Head and 

 prothoracic segment slightly chitinous, rest of segments some- 

 what leathery. Whole larva nearly same width, but a little nar- 

 rowed anteriorly on abdominal segments. Head rather rounded 

 in outline, mottled with pale brownish in three areas on posterior 

 half, about same width as prothoracic segment. Thoracic seg- 

 ments very short, about one-thire as long as wide, the posterior 

 two somewhat wider than the prothoracic. Segments 5 to 9 

 much elongate, about twice as long as wide; 10 but little longer 

 than wide; 11 and 12 about half as long as wide; anal (13) 

 slightly longer, with a dorsal shield rapidly narrowed and 

 rounded behind, two anal tubercular projections immediately 

 beneath tip of latter, and the anal prolegs springing from beneath 

 sides of shield-like dorsum. Head and thoracic segments with a 

 lew hairs; the elongate abdominal segments with about four 

 dorsal and four ventral very short and inconspicuous hairs. All 

 the segments, except prothoracic, head and anal, more or less 



