THE THORAX. 71 



II. THE THORAX. 



73. 



THE second chief division of the body of an insect, and which 

 succeeds to the head, and is connected with it by the neck, and 

 precedes the abdomen, is the THORAX (thorax, stetkidium*). In 

 calling this portion of the body the thorax, we differ from other 

 writers, who apply this name to parts only of this division of the body ; 

 but why we do so is readily explained to those who remember the note 

 to 9, II, and who agree with us in the rule we there lay down f. 



Fabricius divided the body of an insect into capitt, truncus, abdomen. 

 and artus. That this subdivision is inadmissible, is sufficiently ex- 

 plained at the above-cited place. How this, his iruncus, our thorax, 

 again consists of several divisions, will be more fully shown below. 

 These segments, or divisions, he named in the following words : 

 truncus inter caput et abdomen constat thorace, scutello, pectore, 

 sterna \. He called the upper part of the trunk thorax ( 8) ; pectus 

 was the part beneath, corresponding with the thorax ( 10, page 25) ; 

 sternum, lastly, the central longitudinal line of the breast ( 11). The 

 term thorax, which Fabricius used sometimes for the dorsal superficies 

 of the anterior segment of the trunk, as in the Coleoptera, Orthoptera, 

 and sometimes for the whole superior surface of the trunk, as in the 

 Hymenoptera and Diptera, was afterwards applied to that whole 

 division of the body whose superior surface it was intended only to 

 indicate; and thence sometimes meant the entire anterior segment, 

 and sometimes the whole trunk. Illiger sought to put a stop to this 



* This term, used by Illiger, Bouclie, and others, is less applicable than thorax, because 

 it is borrowed from the Greek (derived from o-<rj9-of), whilst caput and abdomen are Latin. 

 It is true, indeed, that thorax also originates from the Greek, but was long used by the 

 Latin writers of the best period. 



f- Passing over other authorities, we will merely cite in support of our opinion, Cli. L. 

 Nitzsch. See Germar, Magas. der Eut. iii. band, p. 275, note, who there explains 

 himself upon the subject. 



; Philos. Entoni., p. 22, 7. 



