MORPHOLOGY OF THE BRAIN 



229 



If the tongue (ligula, or hypopharynx) represents a distinct pair 

 of appendages, then there are seven segments in the head. 



m x 



FIG. 246. Section through head of a carabid, Anopthalmus telkampfti : br. brain ; ./(7,frontal 

 ganglion ; soe, suboesophageal ganglion ; co, commissure ; n. I, nerve sending branches to the 

 lingua (1) ; nm, maxillary nerve; mx, 1st maxilla; mm, maxillary muscle; in:f', 2d maxilla; 

 mt, muscle of mentum ; le, elevator muscle of the o?sophagus ; I', of the clypeus, and a third beyond 

 raising the labrum (Ibr) \ t-ph, epipharynx ; g. g', salivary glands above; gr 2 , lingual gland b'elow 

 the oesophagus (ce) ; in, mouth ; pv, proventriculus ; md, mandible. 



The brain, then, supplies nerves to the compound and simple 

 eyes, and to the antennae, and gives origin to the sympathetic 



net nr d <jf e 



no 



Ibr 



(b 



FIG. 247. Median longitudinal section through the head of Elatta orientals. The nervous 

 system of the head is drawn entire, hyp, hypopharynx ; on. oral cavity ; Ibr, upper lip ; gf, frontal 

 ganglion ; g, brain ; na, root of the antennal nerve ; no, root of the optic nerve ; ga, anterior, (jp, 

 posterior ganglion of the paired visceral nervous system ; o, oesophagus ; a, oesophageal commis- 

 sure ; us g, infraoesophageal ganglia ; ce, longitudinal commissure between this and the first thoracic 

 ganglion ; xy, common duct of the salivary glands ; ib, labium (2d maxillae) ; nr, recurrent nerve ; 

 d, nerve uniting the frontal ganglion with the oesophageal commissure ; e, nerve from this commis- 

 sure to the labrum; f, nerve from the infraoesophageal ganglion to the mandible, g, to the 1st 

 maxillae, A, to the lower lip (2d maxillae). -After Hofer, from Lang. 



nerves ; it is thus the seat of the senses, also of the insect's mind, 

 and coordinates the general movements of the body. 



