1974] 
Burns — Polytypic Genus Celotes 
55 
slightly flared tip with a peripheral array of fine sharp teeth (fig. 
4A-C). Its homolog in nessus is a robust spike arising in a similar 
position, except that the distinctive high dorsal curvature of the body 
of the valva in nessus places the origin of the spike well down on the 
medial surface of the valva (fig. 3A-C) ; this tapering spike extends 
chiefly dorsad, but usually bends slightly caudad at its apex, which 
is pointed and often entire or bifurcate (fig. 3A,B), but sometimes 
trifurcate, or very rarely quadrifurcate ; although occasionally broad- 
ened or lengthened and bent strongly caudad apically, the spike never 
approaches the form of the spatula in limpid. (2) Anterior end of 
tegumen, in limpid , large and well-developed, projecting far cephalad 
(fig. 4E,F) ; but in nessus, extraordinarily reduced (fig. 3E,F). 
(3) In limpid, uncus broad, and the paired terminal prongs of the 
uncus heavy and stubby (fig. 4F) ; but in nessus, uncus relatively 
narrow, and its terminal prongs more delicate (fig. 3F). 
Femule genitdlid. — Fig. 6. Sterigma of limpid altogether more 
massive (fig. 6A,B) and, viewed ventrally, more nearly square in 
outline (fig. 6A) ; heavy central sclerotization in lamella postvagi- 
nalis like a wide triangle tapering quickly toward ostium bursae 
(fig. 6A). Sterigma of nessus (fig. 5) less massive (fig. 5A,B) and, 
in ventral view, narrower posteriorly, suggesting in outline a cau- 
dally truncated triangle (fig. 5A) more than a square; heavy central 
sclerotization in lamella postvaginalis limited to a comparatively 
narrow midventral strip that tapers but little toward ostium bursae 
(fig. 5A). Ostium bursae of limpid a relatively narrow curved slit, 
like a crescent bowed dorsad (fig. 6C), but that of nessus large and 
more or less round, like a manhole (fig. 5C). 
Spdtidl distribution. — A widespread species, nessus ranges from 
about the 97th meridian in southcentral Oklahoma and central Texas 
west to northwestern and southeastern Arizona and south in Mexico 
to at least southern Sonora, southern Chihuahua and Coahuila 
(fig. 7). By contrast, so far as known, limpid occurs only along the 
southern Rocky Mountain axis in Trans-Pecos Texas and along the 
Mexican counterpart of this axis, the northern segment of the Sierra 
Madre Oriental, as far south at least as southern Coahuila (fig. 8). 
Having been taken in numbers in the Guadalupe, Davis, and Chisos 
mountains of Trans-Pecos Texas, limpid may confidently be expected 
(1) in many other west Texan ranges — such as the Delawares, 
Chinatis, and Santiagos — that are more or less associated with the 
scattered southern Rocky Mountain system, (2) northward in at 
least the New Mexican extension of the Guadalupes, if not in the 
Sacramentos and more northern chains, and (3) southward in Chi- 
