Dr. T. A. Cliapuian's Notes on Xylcborus disjmr. lUl 



We found that the female beetle makes the burrows, 

 and ejects the gnawed wood uneaten. The larvae live 

 entirely on the fungus (" ambrosia ") that grows in 

 them. 



When young they are straight, but not flounder-shaped, 

 like those of Platyinis cylindrus. When older they are 

 curved and look not at all like Platypus, but very similar to 

 those of other Scotylids or even ordinary Rhynchophora. 

 Their jaws are pointed for scraping and tearing, and 

 contrast with the pointed mandibles of bark beetles. 



It may be noted that we saw no traces of beetles 

 attacking anything but (recently) dead or dying timber, 



Fig. 3. — Jaw of larva of X. dispar, compared with 

 that of Scohjtus multistriatus. 



and considering that they live not on the wood but on a 

 fungus, it seems impossible they could live in healthy 

 timber, even if Hubbard is right, in supposing that the 

 beetles are able to plant and cultivate the fungus. On 

 examining the larva3 after our return home, I was much 

 interested in finding that they had a very remarkable 

 structure in connection with the spiracles. 



In a little longitudinal oval hollow there lies flatly 

 against the surface what looks at first like two somewhat 

 elaborated lips of an ordinary spiracle. If they were so 

 the opening would be longitudinal instead of transverse. 

 These two apparent lips, however, appear to be two 

 parallel lobulated sacculi free at their posterior ends, but 

 united together anteriorly where they are connected with 

 a circular skin area, which is probably the true spiracular 



