The Basal Sclerites of the Leg in Insects. 19 



the distal trochanter is a portion of the femur demarked by a con- 

 striction, and Vekhoeff, 1902, arrived at the same conclusion from 

 his study of the musculature. Veehoeff considers that the distal 

 region of tlie trochanter of insects (which he terms the praefemur) 

 is the homologue of the femur of Chilopods, while the proximal 

 region of the trochanter of insects, he thinks represents the true 

 trochanter. This view, however, is combatted by Gruenbekg and 

 BoERNEE. Gruenbeeg interprets the division of the trochanter into 

 two regions in the Odonata, etc., as the result of the formation of 

 an internal ridge for the stiifening of the trochanter, and states 

 that the two regions thus formed in the trochanter of the Odonata 

 are not strictly homologous with the two subdivisions of the tro- 

 chanter of such insects as Machilis. 



According to Boedage, 1898, the trochanter was originally a 

 distinct segment in the ancestors of the Phasmids, but, due to the 

 stress and strains experienced by these insects in the process of 

 moulting (during which the legs are frequently pulled oif) the region 

 between the trochanter and femur became hardened and more 

 strongly chitinized, leaving merely a constriction demarking the 

 trochanter from the femur. It is impossible, however, in the present 

 state of our knowledge concerning it, to decide as to the correctness 

 of these theories concerning: the nature of the trochanter. 



2* 



