TOMICID.E. 245 



Genus 216. TRIOTEMNUS. 

 WoUaston, Cat. Can. Col. 264 (1864). 



As Dr. Crotch's original specimen, for the reception of which I 

 established this genus in my Canarian Catalogue, happened to be a 

 female one, I had no opportunity of detecting the singular and most 

 anomalous character afforded by the opposite sex, and so merely 

 called attention to its 3-jointed funiculus, the subretuse apex of its 

 elytra, and sundry other secondary features which served to distin- 

 guish it from the immediately allied groups. But further material 

 has now disclosed to me a sexual peculiarity of a kind which I have 

 never before witnessed (so far as I can recollect) in any member of 

 the Coleoptera namely, that the males (in which the forehead 

 appears to be concave) have a small and incurved, but upwardly- 

 inclined, horn, or tooth (more or less expressed in different indi- 

 viduals), on the outer face of their mandibles ! Had this process 

 been a development of the front edge of the clypeus there would 

 have been nothing very remarkable about it ; for although such a 

 structure is not usual in the Tomicidce, it at any rate obtains in the 

 male sex of the various forms around Cls (of the preceding family), 

 the frontal tubercles of which frequently present much the same 

 appearance, at first sight, as these mandibulary processes of Trio- 

 temnus ; but to be placed where they are, on the upper surface of the 

 mandibles, is quite without a precedent in any insect with which I 

 am acquainted. 



687. Triotemmis subretusus. 



Triotemnus subretusus, WolL, Cat. Can. Col. 265 (1864). 

 Habitat Canarienses (Ten., Gom.}, in plantis Euphorbice canariensis 

 antiquis aridis emortuis a DD. Crotch deprehensus. 



Found first by Dr. Crotch in Gomera, during his Canarian cam- 

 paign of 1862, and subsequently by himself and his brother (in 

 tolerable abundance) both in that island and Teneriffe. Mr. G. R. 

 Crotch informs me that they met with it only in the dry but rotten 

 stalks of the Euphorbia canariensis. 



Genus 217. LIPARTHRUM. 

 Wollaston, Ins. Mad. 294 [script. Leiparthrum] (1854). 



688. Liparthrum mandibulare. 



Leiparthrum mandibulare, WolL, Ins. Mad. 295, tab. v. f. 9 (1854). 

 -, Id., Cat. Mad. Col. 97 (1857). 



Habitat Maderenses (Mad.), sub corticc in castaneto quodam cap turn. 



