'27'2 ANATOMY. 



I. THE BRAIN. 

 183. 



The brain (encephalum*) of insects consists of two ganglia, one of 

 which passes over the pharynx and the other beneath it * ; both are 

 connected by means of nervous cords, which run from the upper to the 

 under, and which embrace the oesophagus. I consider that which lies 

 above as the cerebrum of the higher animals ; the lower one, on the 

 contrary, as the cerebellum : and, indeed, because, as in the higher 

 animals, the nerves of the superior organs of the senses, namely, of the 

 eye, spring from the upper ganglion ; and from the lower one, on the 

 contrary, the nerves of the mandibles, lips, and tongue proceed. It 

 must not appear strange that the nutrimental canal passes through the 

 brain, particularly as the entire spinal cord lies beneath the intestinal 

 canal, and that the entire dorsal side of the higher animals is transferred 

 to the ventral side of insects. We are convinced of this by the situation 

 of the limbs and their connexion with the thorax, which also takes place 

 at the ventral side, whereas, in the superior animals, they pass from 

 the back, and, besides, the structure of the plates of the breast, which so 

 completely imitate the spine of the superior animals that no doubt can 

 be fairly entertained of their analogy, and of which we shall speak 

 more fully below. But whosoever should think the assertion absurd 

 that the oesophagus passes through the brain, we will merely remind him 

 of the certainly still more striking circumstance in the mollusca, in 

 which the colon passes through the heart, an assertion which has found 

 no contradiction, although both organs in the higher animals are far 

 more distant from each other than the brain and oesophagus. 



184. 

 THE CEREBRUM. 



The cerebrum (PL XXXI. and XXXII. A, A, A,) is a nervous cord 

 of a yellowish white colour, lying transversely across the oesophagus, 



* J. Miiller asserts of Phasma gigas, that the brain lies beneath the oesophagus (Nova 

 AcUe, T. xii. Pt. 2. page 568), which I much doubt, notwithstanding my conviction of the 

 general perfect accuracy of his investigations. He distinctly describes the cerebellum , and 

 he has overlooked the cerebrum, which lies over the resophagus. 



