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Psyche 
[June 
by one of us, but the particles were often impossible to identify. 
The larval gut contents of the Euxestus from bat guano contained 
a variety of hyphal sections and spores, while numerous darkly- 
pigmented spores of a single type were found in the adult proven- 
triculus of a Philothermus collected under pine bark in Mexico. The 
proventriculus of Ceryhon castaneum collected on dried mushrooms 
from a tree was filled with sculptured basidiospores, while that of 
the same species taken under conifer bark contained sections of 
hyphae, as well as spores. Those forms with piercing-sucking mouth- 
parts have been assumed to be predators (Besuchet, 1972), but 
as yet there is no direct evidence supporting this hypothesis (see 
below) . 
Perhaps the most interesting feature of the subfamily Ceryloninae 
is the occurrence of piercing-sucking mouthparts in all known larvae 
and in adults of over 50 species in at least six genera. This condition 
may have evolved twice in the larval forms and several times in the 
adults (see below). The most highly specialized type of piercing 
apparatus in adult cerylonids occurs in the genus Cautomus and has 
been described and illustrated by Besuchet (1972). In this group, 
the labrum-epipharynx and the labium together form an elongate, 
tubular beak, in which are contained four pairs of stylets, each set 
consisting of a mandible and its lacinia mandibularis (prostheca), a 
galea, and a lacinia. The molar area of the mandible is absent, while 
both the mandibular apex and the prostheca are long and blade-like. 
The maxillary stylets are extremely long and thin and are attached 
to a basal fulcrum which allows them to be protracted; the lacinia 
bears fine recurved teeth and the galea is provided with hairs at the 
apex. Finally the pharynx is enlarged, forming a pharyngeal pump. 
This type of condition also occurs in Axiocerylon and its relatives, 
in the New World Cerylcautomus, and in a few species of Lapethus. 
Although the mechanics have not been studied, it is obvious that this 
represents a piercing-sucking organ similar to those found in various 
Diptera and Hemiptera. 
Besuchet (1972) also discussed the transition from normal chew- 
ing mouthparts found in Cerylon to those in Cautomus through 
forms such as Ectomicrus , which exhibit an elongation of the labrum, 
mandibular apex, galea, and labium. The same type of intermediate 
condition may be found in species of Lapethus (figs. 11-12) and in 
certain Philothermus. In most of these species, the labrum and 
labium are somewhat elongate, the galea and lacinia are both stylet- 
like, the mola is usually present, and the mandibular apex retains two 
