264 



PTILOTA : IMAGO — EXTERNAL ANATOMY. 



Entomology," wherein, although Messrs. Kirby and Spence 

 do not describe much more than twenty of its distinct com- 

 ponent parts, about forty different words are used for them 

 in the nomenclature of the thorax. The chapter on Oris- 

 mology is nevertheless, as Mr. MacLeay observes in the 

 Zoological Journal, " more particularly valuable, and, making 

 allowance for the nomenclature of parts, deserves the special 

 attention of entomological students." 



Much of this confusion has been obviated by M. Audouin, 

 who, from his admirable comparative investigation of the 

 structure of the segments of the body, ascertamed that they 

 were respectively composed of the same essential parts, and 

 consequently that the same series of names might be applied 

 to each. The folloAving is a table of the thorax, as theo- 

 retically supposed by him to exist in all insects. 



Thorcu. 



(Truncus, 

 Linn., Fabr. 

 and Kirby). 



Prothorax. 



(Manitrunk, 



Kirby; 



Corselet, 



Strauss). 



Mesothorax. 

 (Meditrunk, 



Kirby ; 

 Prothorax, 



Strauss). 



Mefathorax. 



(Protrunk, 



Kirby and Sp.; 



Metathorax, 



Strauss). 



fPraescutum. 

 J Scutum. 

 I Scutellum. 

 LPostscutellum. 



r Sternum, 

 j Episterna. 

 1* * * * 



L Epimera. 



Tergum. "1 

 (Pronotum, 

 Burmeister; 

 Prothorax, 

 Kirby). Tl. J 

 Pectus. i 

 (Prosternum, 

 Burmeister ; j 

 Antepectus, j 

 Kirby). (T) 2. J 

 Furca, called Antefurca. 



Medipectus, | £;^'"f- 

 Kirby). (T) 2. J >-^P""e»a. 

 Furca, called Medifurca. 



(.Sotum, Xll^T-^ 

 Burmeister; M geu eUum 

 Sy}!'T3: J Iposlsiuteli. 



(MSst'enuim,! fP^^aptera 



Burmeister ; 



Postpectus, 

 Kirby). (T)3. J 

 Furca, called Postfurca. 



► Tl 



horh 1 

 i or i 1 



kor k 1 



J Sternum. 

 I Episterna. 

 t Epimera. 



a or a 2 

 bor b2 

 c or c 2 

 d or d 2 



her h2 

 i or i 2 

 kork2 



a or a 3 

 b orb3 

 c or c 3 

 dord3 



h or h 3 

 i or i 3 

 k or k 3 



