28 PROCEEDINGS OF THE ACADEMY OP [Jan., 



the piece termed the "antecoxal piece" in Comstock's, '95, figure of 

 Enchroma gigantea (page 503). In the latter case, the antecoxal 

 piece corresponds to that portion of the sternum which will be later 

 referred to as the furci sternum. The writer was not able to discover 

 the original use of the expression, but as early as 1861, Leconte, in 

 his classification of the Coleoptera of North America, states that a 

 pair of "horny plates" is found embedded in the membrane of the neck, 

 and terms these the "antecoxal plates." The plates here referred to 

 are evidently the cervical sclerites. 



As has been mentioned, Comstock, '02, designates the antecoxal 

 trochantin (pi. Ill, T & ) the antecoxal piece. On the other hand, he 



refers to the coxal trochantin as the entire trochan- 

 tin. The latter usage, however, is quite incorrect, 

 for the coxal- and antecoxal-trachantin together 

 form the trochantin, and it is in this sense that 

 the term will be used in the following discussion. 

 Corresponding to the external (trochantinal) 

 Fig. 14. — Streb- suture, dividing the trochantin into the coxal and 



lognathus (after antecoxal regions, is an internal ridge which may 



Janet). — A com- ° ° 



parison with fig. be termed the endotrochantinal lamella, and the 



13 shows the way thorn-like process near it may be termed the endo- 

 m which the cer- c 



vico-propleura trochantinal process. 



(C-Pl)^ become Svnonyms for the term trochantin are Voss', 



approximated on , n t~v 



the ventral sur- '04, prsecoxal plate, and Strauss- Durkheim s, 



face and com- > 2 8, rotule. The term prsecoxal plate has little 



pletely conceal . 



the presternum. to recommend it, but it would have been much 



preferable if entomologists had adopted the term 



rotule ; for the latter term better expresses the function of this sclerite, 



is not borrowed from vertebrate anatomy, and is not so confusingly 



similar to the term trochanter, as is the case with Audouin's trochantin. 



However, the name trochantin, or the latinized form trochantinus, 



given it by MacLeay, '30, is a very useful term and has received too 



wide an acceptance to attempt to change it. 



Between the trochantin and the coxa lies a very small chitinous 



plate, the complementary coxal sclerite, 11 or "complementary plate" 



(Borner, '03), which bears an internal process, the complementary 



process, to which are attached certain muscles extending to the epi- 



sternum. This small sclerite is frequently fused with the coxa, and the 



complementary process then appears as a process of the coxal margin. 



11 The accessory coxal plate of Snodgrass, 'OS. 



