1975] 
Lawrence £sf Stephan — Cerylonidae 
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or three small teeth, which appear to interlock with those of the 
opposite mandible. This type of mandible resembles that found in 
Collembola, and it may function in a similar way, with the apical 
teeth pulling hyphae or strands of wood into the mouth, where they 
are acted upon by the mola (Folsom, 1899; Macnamara, 1924). The 
maxillary lobes, although very long and stylet-like, have numerous 
fine hairs which may serve to gather spores or other particles into 
the mouth cavity. These mouthparts are somewhat similar to those 
found in the rhypobiine Corylophidae (Paulian, 1950). In Rhypobius 
and its relatives, the maxilla has a single stylet, the mandible is 
divided, with a basal fulcrum and a long hooked apex, and both are 
enclosed within the head cavity when not in use. 
The larvae of cerylonines have two different types of feeding 
mechanism. In Philothermus and Lapethus , the labrum and labium 
form a tubular beak, while the mandible and the mala are both 
modified into long, blade-like stylets. In addition, the pharynx is 
enlarged and a pair of salivary glands extend back into the thorax 
for a distance equal to the head length. These, like the Cautomus 
adults, have a well-developed piercing-sucking apparatus. The larval 
head, however, is strongly hypognathous, and not prognathous like 
that of the adult. The second type of feeding apparatus is found in 
the larvae of Cerylon. Here the head is opisthognathous with the 
labium short and fused to the thorax, and the mandibular and max- 
illary stylets completely enclosed within the head and apparently 
attached to a heavily sclerotized internal framework. This condition 
is remarkably similar to that found in the entognathous apterygote 
insects, such as the Diplura, Protura, and Collembola (Tuxen, 1959). 
As mentioned above, the actual food source of these small and 
uncommon insects is often difficult to ascertain, and this is especially 
true for those species ingesting fluids, if this is the case. Although 
it would be an obvious conclusion that those cerylonids with piercing 
beaks are predators on small arthropods and nematodes, it is also 
possible that the beaks penetrate wood or fungal hyphae or that these 
substances are digested extra-orally. Another possibility is that spores 
or other objects less that 5 or 6 microns in length are moved into 
the labral-labial tube by suction or by the action of the setiferous 
galea; the apical openings of those beaks examined were at least 8 
microns wide. Another matter to consider is the normal position of 
the head. In most of the adults with piercing beaks, the head is 
somewhat prognathous, so that predation would be possible on active 
prey species of various sizes. Most cerylonine larvae, however, are 
