562 CAROLINE B. THOMPSON 



The parts of the brain 



I. The supraesophageal ganglion. 



A. Protocerebrum 



The protocerebral lobes 



_,,,,, . J anterior, dorsal 



The protocerebral commissures < .11 

 [ posterior, dorsal 



[anterior roots 

 The mushroom bodies -! central body roots 



[porterior roots 

 The central body 

 The optic lobes 



B. Deutocerebrum 



The antennal lobes 



C. Tritocerebrum 



The tritocerebral lobes 



The tritocerebral commissure (subesophageal) 



II. The subesophageal ganglion 

 The ventral connectives 

 The mandibular 



The maxillary f gangli 

 The labial 



The nerves of the head 



A. The optic nerves 

 The ocellar nerves 

 The fontanel nerve 



B. The antennal nerves 



C. The labrofrontal nerves to [the nerve to the protocerebrum 



the frontal ganglion i the labral nerves 



[the recurrent nerve 



The mandibular nerves 

 The maxillary nerves 

 The labial nerves 



the subesophageal ganglion, sb.g., are drawn from sections of 

 the same form.* 



* The heads of all termites are held in a somewhat slanting position, making 

 a large obtuse angle with the long axis of the body, so that the morphologically 

 dorsal surface of the head has become frontal or anterior. The slant of the head 

 is much less in termites than in ants, and in the termite soldier the head is almost 

 horizontal, the so-called frontal surface being practically dorsal, but for the 

 sake of clearness the same terms of direction will be applied to all the castes of 

 termites. In describing the entire heads the terms anterior and posterior imply 

 toward and away from the frontal surface, in the same sense that Hesse (1901 b) 

 uses the terms rostral and caudal ; in like manner dorsal and ventral imply toward 

 or away from the vertex of the head. 



