16 



BULLETIN 1218, U. S. DEPARTMENT OF AGRICULTURE. 



large fleshy top region, developed as receiver for the distal division, and of a 

 much smaller, strongly chitinized basal region; this latter contains the proc- 

 esses with the mandibular dorsal fossa and the ventral condyle, which articu- 

 late, respectively, with the dorsal and ventral articulating processes from the 

 antero-lateral margin of the head capsule. The tendon of the interior mandi- 

 bular muscle (=abductor or flexor mandibularis) extends from the inner cor- 

 ner of the basal region, and the exterior mandibular muscle (=abductor or ex- 



Fig. 12. — Mature larva of Tabanus punctifer. A, Anterior part of head from below ; 

 ant, Antenna ; yl, glossa ; gu, gula ; labi, subnientum, mentum, and stipes labii 

 fused into small transverse membranous area. B, Anterior part of head from 

 above: afr, Angulus frontalis ; ant, antenna ; cl, clypeus; la, labrum. C, Anterior 

 part of head from side: a, Antenna; afr, angulus frontalis; ca, eardo : ep, epi- 

 pharynx ; epic, epicranium; gu, gular plate; la, labium; lac, 1 acini a ; lig, ligula 

 (glossa) ; Ip, labial palp ; md, mandible ; p, maxillary palp ; pf, maxillary palpifer ; 

 st, maxillary stipes. Drawn by H. B. Bradford under supervision of Adam G. 

 Boving. 



tensor mandibularis) is, as previously mentioned, attached to the chitinous rod 

 in the membranous process formed by the combined mandibular articulating 

 membrane, membi'anous angulus frontalis, and antennal articulating membrane. 

 Maxilla attached to epicranium along the hypostomal margin. Cardo and stipes 

 hardly separated. Cardo whitish, entirely membranous, not much smaller 

 than stipes. Stipes yellowish, divided into three sclerites of subequal size and 

 more or less of subtriangular shape ; one sclerite ventral and posterior, prob- 

 ably stipes maxillje ; the second, ventral and anterior, possibly palpifer ; the 



