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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXVI. 



the higher insects, develops into a scale-like lobe overlapping the 

 base of the wing. In such cases it is known as the tcr/uJa, but this 

 name is used in the present paper to designate both the well-developed 

 tegula of the Lepidoptera, Hynienoptera, and Diptera, and its pad- 



FiG. 5. — Diagram of a cknekalized wing and its auticulau sclerites or axillaries : 



1 A, FIRST A.NAL VEIX; AF, FIRST AXAL FOLD; 1 Ax, 2 Ax, S Ax, // Aw, FIRST;, SECOND, 

 THIRD, A.ND FOURTH AXILLARIES; AxC, AXILLARY CORD; Ax3I, AXILLARY MEMBRANE; C, 

 COSTA ; Pit, CTBITUS ; 21, MEDIA ; /•', RADII'S ; (S'c, SUBCdSTA ; 7V/, TEiil'LA. 



like representative in other orders. The posterior free margin of 

 the axillar}^ membrane is thickened in such a way that it has the 

 appearance of being a corrugated cord attached to the posterior 

 angle of the notum. It is here called the axiUary cord (AxC). 



Fig. G. — Diagrammatic cross section of a wing-bearing segment; ANP, anterior 



NOTAL wing process ; 1 Ax, first AXILLARY ; :2 Ax, SECOND AXILLARY ; Cx, COXA ; CxI', 

 COXAL PROCESS OF PLEUUDM ; Fc, FURCA (ENTOSTEENUM) ; N, NOTUM ; PA, PLEURAL ARM ; 

 PR, PLEURAL RIDGE (ENTOPLEURUAI ) ; ,9, STERNUM; W, WING; WP, V/ING PROCESS OF 



PLEUra'M. 



Occasionally some of the four principal axillaries are subdivided 

 and sometimes there occur small extra chitinizations in the axillary 

 membrane. Thus confusion has arisen through different authors 



