1916] Thoracic and Cervical Sclerites of Insects 79 



The pleural suture is always present, together with the 

 apodeme, and they are probably formed by the infolding 

 of the integument due to muscular stress or similar causes. 



The pleuron may be connected dorsally with the tergum 

 at its anterior and posterior end by a bridge and ventrally with 

 the sternum in a similar manner. 



The episternum and epimeron are subdivided into an upper 

 and lower region in some insects. {Mantispa). 



The sternum is composed of five subdivisions in a few 

 insects. {Capnia, Ectobia, etc.) 



The presternite is present as a large, oval sclerite, lying in 

 front of the prothoracic verasternite in Capnia and Forficiila. 

 It is considered as a large ventral cervical by most writers. 



The large sclerite which lies in front of the coxa in the 

 prothorax of sawflies, is largely composed of the lateral cervical, 

 fused with the episternum, and in some cases with the epimeron 

 also. 



The cervical sclerites are detached portions of the head 

 and prothorax and are homologous with the intersegmentalia, 

 which are probably derived from the segments directly anterior 

 and posterior to them. 



In some insects the coxa is composed of two parts, the 

 meron or posterior portion and the veracoxa or anterior portion. 

 The meron is part of the coxa and derived from it. 



BIBLIOGRAPHY. 



1885. Amans. Comparaison des organes du vol dans la serie animale. Ann. Sci. 



Nat., VI ser., ZooL, T. XIX. 

 1820. Audouin. L'anatomie comparative des parties solides des insects. Pre- 

 sentee par M. Cuvier. Ann. Gen. Sci. Phys., T. VII. 

 1824. . Recherches anatomiques sur le Thorax des animaux articules. 



Ann. Sci. Nat., T. I. ser 1. 

 1832. . Exposition de l'anatomie du Thorax. Par. W. S. Mac Leay 



Accompagnee de Notes par M. Audouin. Ann. Sci. Nat., T. XXV, ser 1. 

 1893. Banks. Notes on the Mouth Parts and Thorax of Insects. Am. Nat. 

 1904. . Notes on the Structure of the Thorax and Maxillae of Insects. 



Proc. Ent. Soc. Washington, Vol. VI. 

 1906-09. Berlese. Gli Insetti. Milan, 1906. 

 1903. Borner. Kritische Bemerkungen iiber einige Vergleichendmorphologische 



Untersuchungen K. W. Verhoeff's. Zool. Anz., Bd. 26. 

 1882. Brauer. Ueber das Segment mediaire Latreille. Sitzb, Kais. Akad. Wiss. 



Wien.-Math. Nat. Klasse, Bd. LXXV, Abt. 1. 

 1832. Burmeister. Handbuch der Entomologie. Berlin. 



