1966] 
Lawrence and Reichardt — Ptinidae 
31 
meier presented us with a specimen representing another undescribed 
species. This led to a comparative study of ptinid myrmecophiles, 
part of the results of which are presented below. 
Since both Gnostus and Fabrasia have been made the types of 
subfamilies, it might be well to briefly discuss the classification and 
possible evolutionary origins of the two groups. Gnostus and Fabrasia 
differ considerably from any other group myrmecophilous ptinids in 
general form and in the presence of fully developed wings and hu- 
meral callosities; in this respect they are both similar to certain 
species of the genus Ptinus. They do resemble the Old World 
myrmecophiles in the modifications of the antennae, presence of 
glandular areas or trichomes, elongation of the clypeus, and reduc- 
tion of body hairs or scales, so that the surface appears shiny; most 
of these similarities probably represent adaptations associated with 
myrmecophilous habits, and similar trends are found in the Paus- 
sidae, the clavigerine Pselaphidae, and other groups of inquilines. 
Although Gnostus and Fabrasia are set apart from the other genera, 
Figs. 1 — 5. Gnostus flondanus Blatchley (from Plantation Key, Florida), 
Fig. 1, dorsal view; Fig. 2, lateral view; Fig. 5, antenna; Gnostus meinerti 
Wasmann (from Barro Colorado Island, Panama), Fig. 3, hind leg; Gnostus 
jormicicola Westwood (lectotype), Fig. 4, hind leg. 
