NERVOUS SYSTEM OF GRASSHOPPER — SCHMITT 



323 



metathoracic dorsal nerve and its connective in Orchelimum is espe- 

 cially interesting, 



Maki describes the thoracic first root or dorsal nerves in Chaiiliodes 

 as arising from the ventral nerve cord, between the ganglia, as shown 

 in figure 4 D. It is, of course, possible that in Chauliodes the dorsal 

 nerve is simply adhering to the nerve cord and lacks an anterior con- 

 nective but the resemblance seen here to the condition in Orchelimum 

 suggests that a dorsal nerve connective occurs in the Sialidae. Ham- 



i^A 



Fig. 4. — Ventral thoracic nerve cords. A, Acheta (Gryllidae). B, Periplaneta 

 (Blattidae). C, Orchelimum (Tettigoniidae). D, Chauliodes (Corydalidae, order 

 Neuroptera) (after Maki), 



mar (1908) illustrates nerves arising from the ventral nerve cord of 

 the Corydalis larva in the same manner. Snodgrass (1925) shows a 

 similar phenomenon in the honey bee. 



An anterior connective of the dorsal nerve in the Lepidoptera is 

 illustrated by Weber (1954) in his figure 104, which he credits to 

 an unpublished drawing by H. Niiesch. According to this illustration, 

 the anterior connective of the dorsal nerve contains motor axones 

 extending from the prothoracic ganglion to the dorsal longitudinal 

 muscles of the mesothorax. 



