PLATE XIX 



Figure 1. 



Figure 2. 



Figure 3. 



Figure 4. 



Figure 5. 



Figure 6. 



Figure 7. 



a. 

 as. 



acs. 



asp. 



dc. 



Idc. 



2dc. 



fo. 



hu. 



ia. 



mp. 



msc. 



npl. 



oc. 



pa. 



ph. 



pr. 



psp. 



psdc. 



psc. 



pt. 



pv. 



sa. 



v, 



Chaetotaxy 



Diagram showing the dorsal thoracic bristles, after 



Williston. 



Thorax of Mitsca dowestica, dorsal side. 



Thorax of Glossina palpalis, dorsal side, after Austen. 



Thorax of Stoiuoxys calcitrans, lateral aspect. 



Thorax of Glossina palpalis, lateral aspect, after 



Austen. 



Diagram of the parts of the thorax, after Mik, from 



Osten Sacken. p., pronotum. s., scutellum. m., 



metanotum. 1. dorsopleural suture. 2. sternopleural 



suture. 3. mesopleural suture, a., mesopleura. &., 



pteropleura. c., sternopleura. d. t hypopleura. e., 



metapleura. I. dorso-humeral region. II. dorsoalar 



region. III. -dorso-central region. 



Head of Musca domestica, seen from above. 



Reference letters, figure 6 excepted. 



Acrostichal or inner dorsocentral bristles. 



Anterior spiracle. 



Apical scutellar bristle. 



Anterior sternopleural bristle. 



Dorsocentral bristles. 



First dorsocentral bristle. 



Second dorsocentral bristle. 



Fronto-orbital bristles. 



Humeral bristles. 



Intra-alar bristles. 



Mesopleural bristles. 



Marginal scutellar bristles. 



Notopleural bristles. 



Ocellar bristles. 



Post-alar bristles. 



Post-humeral bristles. 



Prae-sutural bristles. 



Posterior sternopleural bristles. 



Prae-sutural dorsocentral bristle. 



Prae-sutural dorsocentral bristle. 



Pteropleural bristles. 



Post-vertical bristles. 



Supra-alar bristles. 



Vertical bristles. 



