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which the stomatogastric system (sympathetic system) 
has its origin ( StgNv ). The subcesophageal ganglion gives 
off nerve branches to the mandibles ( MdNv ), maxillae ( MxNv ) 
and labium ( LbNv ). For a study of the minute structure of 
the brain and the paths of the various nervous elements, the 
reader is referred to the works of Kenyon 1 and Jonescu. 2 
In the thorax the number of ganglia is reduced to two 
(Figs. 78 and 84, IGng and 2Gng). The first innervates the 
first pair of legs while the second is a combination of four 
ganglia, as shown by the fact that it innervates the meso- 
1 Kenyon, F. C., 1896. The brain of the bee. Jr. comp, neurol., VI, 
pp. 133-210. 
- , 1897. The optic lobes of the bee’s brain in the light of recent 
neurological methods. Am. nat., XXXI, pp. 369-376. 
2 Jonescu, C. N., 1909. Vergleichende Untersuchungen liber das 
Gehirn der Honigbiene. Jenaischen Zeit. f. Naturwiss., XLV, N. F., 
XXXVIII. 
