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DESCRIPTION OF ILLUSTRATIONS. 
FIG. 
34. wSting apparatus. — A, sheath ; b, part of compound lever ; 
C, second part of lever; D, lever for projecting sheath; 
E, palpi; V, vulva; a, k, lancet; k, barbs of lancet; 
p, poison sac ; g, poison gland 
35. Details of sting apparatus. — B, longitudinal section ; 
A, pouch ; poison gland ; valve ; C, D, E, trans- 
verse sections ; poison channel between lancets ; 
groove ; guide rail ; d’, hollow lancets ; closing 
valves; c, /, lancets; ;2, space between outer and inner 
walls which changes its form in D and E ; F, valve of 
lancet enlarged ; valve ; truss holding valve 
together ; d/, c, lancet ; G, dart, showing barbs, b, and 
poison ducts ; H, sheath, showing barbs, b 
36. Poison, showing oil globules 
37. Spiracle. — <2,/^, cones; r, obturator tendon ; obturator 
muscle ; e, stigmatic vestibule ; f, folded membrane ; 
opening of spiracle 
38. Structure of antenn?e. — A, longiiudinal section; short 
hairs ; conoid hair ; smell hollows ; r/, cavities ; 
joint; y, nerve end cells; bundles of nerves; 
B, hairs on scape ; C, hairs on back of flagellum ; D, tac- 
tile hair in ring, a\ E, conoid hair, b\ F, smell hollow, 
r, with nerve fibre ; G, smell hollow seen from above ; 
H, cavities, d 
39. Wolff’s taste organ on labrum. — ai^ horny ridge; 
sensory pits; c, skin of mouth; d^ e, muscular fibres; 
y g, //, f, k, /, m, section of skin of oesophagus 
40. Wolff’s cups. — a, central hair in cup b) r, ganglionic 
swellings 
41. Undescribed organ. — A, canal; B, cell glands; 5, fifth 
ring ; 6, sixth ring 
42. Sensory organs on palpi. — A, labial palpus; «f, pits; B, 
maxillary palpus 
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