238 



Annals Entomological Society of America [Vol. IV, 



THE SUBESOPHAGEAL GANGLION. 



(Figs. 6 and 7, Plate XVI, Fig. 5.) 

 This ganglion is larger than the others described, and is less 

 flattened and less easy to study from the surface. The branches 

 have already been traced quite well to the periphery and I will 

 only mention them briefly. 



Fig. 6. Fig. 7. 



Fig. 6. Subesophageal ganglion from the ventral side. Methylene blue. x30. 



c connective with brain. 



co commissure 



mx maxillary 



m mandibular 



1 labial 



g gustatory 



Fig. 7. Subesophageal from the dorsal side. x30. 



The caudal portion of the ganglion becomes thick soon after 

 the connectives have entered. The cephalic lateral portion of 

 the ganglion is connected with the supraesophageal above by 

 two large connectives, but smaller than those from the 1st 

 thoracic ganglion. These cephalic connectives or crura cere- 

 bri are connected together a short distance away from the gan- 

 glion by a cross branch or commissure. 



