EXTERNAL ANATOMY OF INSECTS. 3G5 



behind the Nasus, when distinctly marked out. — 

 Ex. Sagra, Prosopis. 



3. Frons (the Front). That part of the Face which 



lies behind the Postnasus, and usually between the 

 posterior part of the eyes. This is sometimes the 

 region of the Stem?7iata ; or they are partly in this 

 or partly in the Vertex a . 



4. Vertex (the Vertex). The horizontal part of the Fa- 



des, next the front, that lies behind the eyes and 

 between the temples b . This also is often the region 

 of the Stemmata. 



5. Occiput (the Occiput). The back part of the head 



when it is vertical, or nearly so, to its point of junc- 

 tion with the trunk . — Ex. Meloe, Ripiphorus, 

 Hymenoptera, Diptera. 



6. Genje (the Cheeks). Those parts which lie on the 



outside of the anterior half of the eyes, and inter- 

 vene also between them and the Mandibular d . 



7. Tempora (the Temples). Those parts which lie on 



the outside of the posterior half of the eyes, between 

 which the Frons and Vertex intervene e . 



8. Oculi (the Eyes). The principal organs of sight, 



most commonly two in number, placed in the sides 

 of the head. In the majority they are compound, 

 consisting of hexagonal lenses. In the Arachnida 

 they are simple f . 

 A Canthus (the Canthus). A process of the face, which 

 enters the notch or sinus of the eye &. — Ex. Scara- 

 bamsL., Cerambyx L. 



9. Stemmata (the Eyelets). Two, or more commonly 



a Plate VL c. b Ibid. d. c Ibid. e. d Ibid. f. 



e Ibid. g. f Plates VI. VII. and XXVI. h. 



E Plate VI. Fig. I. and VII. Fig. 2. h'. 



