AFFINITIES OF THE PRIONIDyE. 285 



this structure is in Macrodontia, where they are greatly 

 porrected, and more than twice as long as the head. 

 These insects fly usually at night, and during the day 

 they are lazily affixed to the trunks of trees. The power 

 of flight,, of course,, implies the possession of wings ; but 

 one genus (Prionapteron) is remarkable for being apte- 

 rous, and having its elytra soldered together. InAnacolus 

 these organs are shorter than the body and the true 

 wings ; and, although the tetramerous tarsal structure 

 is universal among them, yet in Trictenotoma they are 

 heteromerous ; whence M. Solier has combined it with 

 PhrenopateSy another anomalous, genus, but belonging 

 certainly to a different group ; and he has formed with 

 them an introductory section to his distribution of the 

 Heteromera. We, however, think Trictenotoma appears 

 to have a strong affinity to the Lucanidcz, into the 

 circle of which, as an aberrant form, it ought possibly 

 to enter ; of which we have a double indication in the 

 structure of the antennae, which present a very elongate 

 basal joint, and an indication of a lamellated form at 

 the apex. A similar situation might also, possibly, be 

 assigned to Parandra, which the majority of sys- 

 tematists have placed contiguous to the Prionidce ; in 

 their general form, however, particularly in that of the 

 clypeus and labrum, and the thorax, and in the posses- 

 sion of the tarsal plantula and pseudonychia, they are 

 closely related to the Lucanidce, and only want pec- 

 tinated antennae to belong absolutely to that family. 

 But leaving this for future investigation, we have not 

 the least doubt that, by means of the extraordinary 

 Torneutes, a South American insect, nearly three inches 

 long, and not more than half an inch broad, we have a 

 direct intimation of the proximity of Cucujus and its 

 affinities, as Spondylis equally points to the sub-family 

 of the Bostrichidce. The excessively flattened forms of 

 Cucujus, Brontes, Dendrophagus, &c., is admirably 

 adapted for their peculiar economy, living, as they do, 

 beneath the bark of trees. The allied Palcestes and 

 Passandra follow naturally here^ where we think it 



