1963] 
Evans — Cephalonomia 
157 
length ratio .68 and .71, higher than in any other specimens, and in 
having the wings very slightly longer than usual. These are the only 
two of the 27 short- winged females which are somewhat intermediate 
between micropterous and subapterous, though in wing length they 
can be regarded as subapterous. The mean head width/length ratio 
is not plotted on Figure 2, as it is only slightly different from that for 
the apterous females. 
Description of apterous female. — Total length 0.7-1.0 mm. Head 
length .253-. 333 mm.; head width .61-. 68 X head length (mean .64). 
Wings absent, but tegulae of nearly normal size; ocelli barely dis- 
cernible, apparently absent in some specimens. Coloration and sculp- 
turing as in subapterous female, head shape as in that form, the eyes 
even smaller; eyes removed from base of mandibles by .7-. 9 X their 
own height, removed from vertex crest by 2.O-2.5 X their own height; 
minimum width of front 1. 8-2.0 X eye height. Scutellum weakly 
separated from mesoscutum, with a barely perceptible basal groove. 
As may be seen from Table I, apterous females occur in zones C 
(Arizona), D (Sierras of California), and D 1 (Mexico). Specimens 
from all three of these zones are exceedingly similar. Following the 
same trend as in the alate males and females, Arizona specimens 
average the largest, followed by California and Mexican specimens. 
The figures for head length are as follows: Arizona (zone C) .274- 
.333 (mean .297) ; California (zone D) .263-. 304 (mean .290) ; 
Mexico (zone D 1 ) .253-.320 (mean .284). 
Summary of sexual and morphic differences. — The males are 
readily separated from the females by the longer antennae, particularly 
the apical segment, which is more than twice as long as wide in the 
male, less than twice as long as wide in the female. In addition, the 
ocelli are well developed in both alate and apterous males, whereas 
subapterous and apterous females have the ocelli absent or barely dis- 
cernible. Of course, in most females the sting is visible, and in many 
males the apices of the parameres can be seen. 
Apterous males differ from alate males not only with respect to 
the wings, but also in having a decidedly more narrow head, smaller 
eyes, and slightly reduced ocelli. The difference in head shape of the 
two forms is particularly striking when the width is plotted against 
the length, as in Figure 1. It is interesting that the mean head width/ 
length ratio for the apterous males is the same as that for the alate 
females (.72) ; that is, the lower line in Figure 1 is the same as the 
upper line in Figure 2. 
As compared to the alate females, the micropterous females have 
