KXl'LANATION OF TLATK-S VII 1. AND IX. Ill) 



Fig. 14.— Diagrammatic transVcrso section tbrougli the pharynx i)f 

 (llossina ; a, postoiior wall of tho pharynx; b, its anterior wall; c, its 

 lateral wing; d, solid plato in tho opistoma; c, pumping musclos. 



Fia. 15. — Head of Stomoxys sp., 9, from rcmba Island, East Africa; 

 X 12 : I, labium ; p, maxillary palpus. 



Fig. 16.— Outer mouth-parts, in an oxsortcd condition, of StoviM-ys 

 aUcUram, L., 6 (from Denmark) ; x 19 : a, labrum ; b, hypopharynx ; 

 c, labium; ^i, exsortod membranous cono between the outer moutb-i)artH 

 and the solid ohitin of tho head; e, apodome of tho labrum scon through 

 the skin; /, lirm chitin of the head; </, maxillary palpils ; /;, very small 

 solid plate at tho base of the palpus (? rudiment of tho maxilla) ; i, solid 

 vertical sub-median strip in tho opistoma. 



Fig. 17. — Labrum (with its apodcmos) of SIodio.vijs caU'.itra7Ui,Tj., i', , 

 from below; x 19: «, median longitudinal groove; b, strong ebitinous 

 rod, or apodome ; o, mustlo from the free end of this apodemo, to tho 

 lower ond of tho solid pharynx ; d, muscle from tho apodome to tho 

 jiostorior side of the head; <', muscle from the base of the upper wall of 

 the pharynx to the antoiior margin of the pharyngeal wings. (Tho entire 

 length of tho two last-named pairs of musclos is not drawn.) 



Fi(i. 18. — Distal part of the labrum shown in tiic preceding figure, 

 from bolow; x 120: a, lower margin of tho labrum turned inwards; 

 b, tho median groove; c, sensory organ. 



Fuj. 10. — Distal part of the hypopharynx of Slomoxys calcUrans, L., 

 <5 , from tho side; x 120: a, membranous apical portion. 



Fig. 20. — Right labollum of Stomoxys calcUrans, L., S , from tho uuu r 

 side: X 230: a, lower wall divided longitudinally; b, sub-membranous 

 upper margin; c, tho plato in tho bottom and on tho sides of the median 

 groove; rf, plate on the inner side of tho labellum; r, very strong tooth 

 anchyloKod to tho plate of tho labollum; /, elongate ebitinous blades; 

 g, ebitinous rods; //, setiu on tho outer side near the terminal margin. 



Fiu. 21. — Vertical section, a little to one side of tho plane of symmetry, 

 tlnough the lower part of tho head of Slonwxys calcUrans, L., cJ ; x 27; 

 slightly diagrannnatic : a, basal part of the proboscis, from the outer side; 

 /), anterior wall of the membranous cone; c, maxillary palpus; d, obli(iuo 

 ni(iml)ranous part of the opistoma; c, se(!tion through the solid chitin just 

 outside tho opistonnv; /, posterior wall of the nu^nlbrllnouHconc ; (/.section 

 through the solid chitin outside tho occipital foramen: //, left apodemo of 

 the labrum ; i, pharynx ; k, tube from tho lower ond of the solid pharynx 

 to tho labrum-hypopharynx ; i, ccsophagus ; j)t', muscle from the upper 

 wall of the labrum to tho anterior margin of tho pharyngeal wing; 

 m'-, muscle from the apodemo of tho labrum to tho posterior side of the 

 head ; »»•', muscle from the free end of the apodome of tho labrum to tho 

 lower end of the pharynx itself ; m*, muscle from tho proximal end of tho 

 labium to the posterior side of tho head (the upper part of this nmsclo 

 omitted) ; m'', musclo from tho hind wall of tho membranous cone to tho 

 posterior side of tho head outside the occipital foramen ; vi'\ pumping 

 nmsclo; w', musclo from the posterior process of the pharynx to the solid 

 chitin just outside the opistoma; »i", musclo from tho dilatation of the 



