20 THE ANATOMY OF THE HONEY BEE. 



the pleuruin and associated with the under surface of the wing base 

 are several small plates known as the paraptera (/*)." Two lie above 

 the episternum in front of the pleural wing process and are the 

 episternal paraptera or preparaptera {IP and ^P), while one or 

 occasionally two are similarly situated behind the wing processes 

 and are the epimeral paraptera or postparaptera {3P and J^P). The 

 preparaptera afford insertion for the muscle concerned in the exten- 

 sion and pronation of the wdng. 



The coxa {Cx), or basal segment of the leg, is hinged to the seg- 

 ment by a dorsal articulation with the pleural coxal process {OxP), 

 and by a ventral articulation (TnC) with a plate called the trochan- 

 tin (Tn) lying in front of it and connected above wdth the lower 

 end of the episternum (Eps). Hence, while the leg is of course con- 

 tinuous all around its base, by means of membrane, with the body- 

 wall, its movement is limited to a hinge motion by these two special 

 articulations of the chitin. 



The sternum or ventral plate of the segment is not so complicated as 

 are the tergum and pleurum. It is often divided transversely into 

 three parts, however, and some authors say tj'^pically into four. These 

 parts have been named the presternum (Ps), sternum proper (S), 



segments of the thorax or their respective parts. Entomologists have already 

 established the system of referring a part to the front or back of any individual 

 segment by the Latin prefixes pre (or prte) and post as used in " prescutum," 

 " prestei'num," " postscutellum," and " poststernellum." Furthermore, pre and 

 post are so indiscriminately used in English combined with Latin, Greek, and 

 even Anglo-Saxon words that they may be regarded as general property. 

 Hence, in order not to sacrifice an anatomical system, which certainly needs 

 to be fostered in every way, the writer has preferred to sacrifice strict gram- 

 matical rules by applying pre and post, regai-dless of the origin of the noun 

 in the case, to designate anterior and posterior i)arts of the same segment. We 

 already use such hybrid terms as " presternum," " mesotei'gum," and " meta- 

 tergum." 



The name " preepisteninnr" has been applied by Hopkins (Bui. 17, Pt. I, 

 technical series. Bur. Eut., U. S. Dept. Agr., 1909) to a part of the mesepister- 

 num of Dendroctonus — a plate apparently not homologous with the preepisternal 

 element of the thorax in primitive insects. 



'^ The name " parapterum " is taken from Audouin's term para pf ere (,\nn. 

 des Sci. Nat., I. 1824, pp. 97-135, 416^32), and its application, as used by the 

 present writer, is based on Audouin's definition given in his Chapter III, 

 " Considerationes generates sur le Tliorax,'" where he says (p. 122) : " Finally 

 there exists a piece but little developed and seldom observed, connected with 

 both the episternum and the wing. It is always supported by the episternum 

 and is sometimes prolonged veutrally along its anterior margin, or again, 

 becoming free, passes in front of the wing and may even come to lie above 

 the base of the latter. At first we designated this sclerite by the name of 

 Hypopiere but on account of its change of position relative to the wing base 

 we now prefer the name of PARAPTfeRE." The first part of his description leaves 

 no doubt that Audouin referred to the little i)leural plate beneath the front 

 of the wing which is usually very inconspicuous except in carefully dissected 



