Ken YON, The Brain of the Bee. 163 



female are larger than those in the male. Two years later 

 Brandt ( 76) affirmed the same condition to be true for the Hy- 

 menoptera generally. Berger ( 78) agreed with Dujardin and 

 the rest. Dietl (76) was inclined to dissent, and Flogel (73) 

 seemed to consider the roots and stalks as a framework (Ger'ust) 

 for the rest of the cerebral substance. Nevertheless the tabu- 

 lar summary of his study on the different orders that he gives at 

 the end of his paper is of no inconsiderable value in showing the 

 truth of Dujardin 's inference, so far as comparative anatomy is 

 able to do so. The physiological experiments of Faivre ( 57) 

 and others, which have lately been repeated and perfected in the 

 excellent work of Binet (94), are of great value in showing that 

 the seat of intelligent control of an insect's movements is in 

 the dorso-cerebron. Thus far, however, no attempts seem to 

 have been made to determine experimentally the function of the 

 mushroom bodies as parts distinct from the rest of the dorso- 

 cerebron. Experiments are badly needed to complete our 

 knowledge of the structures. 



All that I am able at present to offer is the evidence from 

 the minute structure and the relationships of the fibers of these 

 bodies. This seems to be of no inconsiderable weight in sup- 

 port of the general idea started by Dujardin. For in connec- 

 tion with what was made known by Flogel and those before him 

 and has since been confirmed and extended by other writers, 

 one is able to see that the cells of the bodies in question are 

 much more specialized in structure and isolated from the gen- 

 eral mass of nerve fibers in those insects where it is generally 

 admitted complexity of action or intelligence is greatest. Con- 

 sidering the calyx and the cells above it alone, one finds that 

 according to Flogel neither are recognizable in the Hemiptera, 

 that in Diptera {Tabaniis) and Odonata {AescJinci) the bodies 

 are recognizable from those in the neighborhood only by a 

 slight difference in the size of the cells representing them ; that in 

 Lepidoptera the calyx-cup is very small or entirely absent , that 

 in the Coleoptera {Tenthrido, Cynips) the calyx is not so ex- 

 tended as to be very well recognized as a cup, and that in the 

 Orthoptera the lateral walls of the cup are either very small 



