88 CLAUDE FULLER. 



EXPLANATION OF PLATES III— XI, 



Illusti-ating Mr. Claude Fuller's paper, "■ The Wing Venation 

 and Kespiratory System of Certain South African 

 Tei'mites." 



PLATE III. 



Fig. 1. — Wing venation : Comstock and Needham's hypothetical type. 



Fig. 2. — Hypothetical primitive element of respiratory system ; sp., 

 spiracle ; tr.. tracheal pipe, and its three pi'imary snbdivisions : a. ascend- 

 ing ; h. horizontal ; c, descending trachea. 



Fig. 3. — Hypothetical development of ascending trachea {« of fig. 2) ; 

 au. aa., branches which go to form the dorsal longitudinal trunk. 



Fig. 4. — Spiracles VIII, IX. X, with a.a.a., palisade commissures ; 

 Dl. t., dorsal longitudinal trunk and its cauda. The visceral tracheai 

 are omitted. (D i a gram .) 



Fig. .5. — Hypothetical development of descending tracheae (c of fig. 2) 

 from opposite spiracles, so as to meet and form a ventral commissure. 



Fig. 6. — Hypothetical development of horizontal trachea (h of fig. 2), 

 so as to link up the spiracles and form the spiracular trunk. 



Fig. 7. — Spiracles VIII. IX. X. with the horizontal trachea? united to 

 the descending trachea of each anterior spiracle, illustrating the indirect 

 primary air route from spii-acle to spiracle. (Diagram.) 



Fig. 8. — A transverse section of the system. 



Fig. 9. — Side view of the system, including spiracles II and III, 

 showing the attachment of the Y-shaped trachea of the second and 

 third legs to the spiracular trunk {Sp. t.). and. at ,v.x., the separation of 

 the trachea? in the region of the til^ise. 



Fig. lU. — Section of the system about spiracles X (the last abdo- 

 minal), illustrating the paii-ed visceral tracheae (<>'.v.) from which the 

 palisade commissures seem to arise. 



Fig. II. — Dorsal and lateral parts of the body system, showing the 

 paired dorsal longitudinal trunks, the paired spiracular trunks, the two 

 sets of palisade commissures, and. ,r.x.,v.i>\. the series of buds upon the 

 dorsal longitudinal trunks. 



Fig. 12. — The dorsal longitudinal trunks with the ai-borescent tracheai 

 which develop from the buds (,r.a?.,»'..r. of fig. II) and which pervade the 

 dome of the body. 



