22 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. y] 



In the cockroach, as described by Zawarzin, there are numerous 

 sensory nerve cells of Type II, mostly multipolar, distributed over 

 the vv^alls of the crop. Some of these cells lie free on the outer 

 surface of the epithelium, some are more or less inclosed within 

 the nerve trunks, and others lie beneath the covering membranes of 

 the ganglia. The distal processes of the free cells break up into fine 

 varicose fibrils that terminate between the epithelial cells ; the distal 

 processes of the other cells apparently innervate the neurilemma of 

 the nerves and ganglia. The main axons, in all cases, go to the prin- 

 cipal stomatogastric ganglia where they terminate in neuropile arbor- 

 izations. Zawarzin does not describe sensory nerves ending in the 

 muscles of the crop. 



The alimentary canal of larvae of Lamellicorn beetles, as described 

 by Orlov, is innervated both from the stomatogastric system and from 

 the abdominal ganglia of the ventral nerve cord. In the larvae of 

 Oryctes and Melolontha, there is a nerve ring around the posterior 

 end of the oesophagus, connected by lateral nerves with the oesopha- 

 geal ganglion, from which six equally spaced, parallel nerve trunks 

 go posteriorly on the walls of the ventriculus. From the ganglia and 

 from the nerve trunks there are given ofif numerous ramifying nerve 

 branches, containing both motor and sensory fibers, that spread over 

 all parts of the oesophagus and stomach. 



The sensory fibers, Orlov says, end peripherally in multipolar nerve 

 cells, the terminal processes of which branch into a network of fine 

 varicose fibrils similar to the sensory network beneath the hypoder- 

 mis. The fibrils terminate on the oesophagus and the ventriculus, 

 some in the connective tissue, and some in the sarcolemma of the 

 muscle fibers. Several types of nerve endings on the muscles are 

 distinguished by Orlov. In typical cases, a nervous network sur- 

 rounds the muscle fiber, and the nerve fibrils contain flat swellings 

 from which are given off fine varicose terminal threads with free 

 ends (fig. 9 A) ; in other cases, the nerve fibers end directly in vari- 

 cose branches on the muscles (B) ; while, again, the nerve may make 

 a complicated spiral tangle about the muscle fiber (C). In most 

 cases, the branches of one sensory nerve cell are localized on one 

 fiber, but in some they spread over adjoining parts of several fibers 

 (B). The character of the sensory endings always distinguishes 

 them from the endings of the motor fibers. 



The proctodeum of Lamellicorn larvae, according to Orlov, is in- 

 nervated by abdominal ganglia of the ventral nerve cord, "from which 

 it receives both motor and sensory fibers. On the small intestine 

 the sensory fibers are distributed principally on the connective tis- 



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