EXTERNAL ANATOMY OF INSECTS. 385 



A Epicnemis (the Epicnemis). An accessory joint at 

 the base of the Tibia in many Arachnida, which 

 does not appear to have separate motion a . 



B Molula (the Knee-ball). The convex and sometimes 

 bent head of the Tibia, armed with a horny pro- 

 cess on each side, by which it is attached to the 

 thigh b . 



C Talus (the Ankle). The apex of the Tibia, where it 

 is united to the Tarsus c . 



D Calcaria (the Spurs). One, two, or more moveable 

 spines, inserted usually at the apex of the Tibia; 

 and in many Carabi L., Lepidoptera L., and TricJio- 

 ptera K., in the middle also. They may be regarded 

 as a kind of fingers auxiliary to the Tarsus, and fur- 

 nish often an important character in the discrimina- 

 tion of genera d . 



E Coronula (the Coromda). A coronet or semicoronet 

 oijixed spines observable at the apex of the poste- 

 rior Tibia in Fulgora candclaria, &c. 



f Tarsus (the Tarsus). The Jiftli principal portion 

 of the legs ; consisting in the majority of insects of 

 1 — 5 joints, but in the Phalangidce of sometimes as 

 many as 50 e . It includes the Planta, Digitus, and 

 Solea. 



A Planta (the Instep). The first joint of the Tarsus is 

 so called when it is remarkably long and broad f . 

 It includes the Calx. 



* Plate XXVII. Fig. 21. s" . b Ibid. Fig. 9, 10, 16, 17.*"'. 

 c Ibid. Fig, 34—36. u". 



d Plate XIV. Fig. 6; and XXVII. Fig. 29— 36. v". 

 e Plate XIV. Fig. 5—8; and XXVII. Fig. 44, 45, 62, 63. t". 

 f Plate XXVII. Fig. 25, 26, 41. w'" . 

 VOL. III. 2 c 



