Ken YON, The Brain of the Bee. i6i 



The lighter places between the spots are filled by the fibers of 

 the mushroom body cells alone (fig. 17). 



In the stalk my preparations show the existence of incom- 

 ing fibers resembling the upper ones represented in fig. 28 

 more than any of the others. But details are not sufficient to 

 enable one to determine their origin or the destination of their 

 outer branches any better than, in fact not so well as, those en- 

 tering the anterior root. 



Very nearly the same thing may be said with respect to 

 the fibers entering the inner root. Some of these appear to be 

 connected with the central body later to be described, others 

 seem to come from the opposite lower side of the brain. Their 

 branches in the root are of the same general type as those rep- 

 resented in fig. 21, but the sub-branches are much shorter, 

 more uniform, and end in a very much more compact head of 

 branchlets. These of course cause the longitudinal banded ap- 

 pearance already mentioned. 



Besides these six or seven groups of entering branches 

 there are to be found numerous fibers irregularly branching over 

 the surface or near the surface of the roots, which may also send 

 small branches into them (fig. 22, PI. XXI), and here may be 

 noted a fiber seen in one section only that is of no little in- 

 terest. Whether it belongs to any of the regular groups I am 

 unable to say definitely, but think from its appearance that it 

 must be a branch of one of the irregular fibers just mentioned. 

 It is figured on plate XXI (fig. 25). It enters the right ante- 

 rior root near its terminus from some little distance in the lateral 

 part of the brain and is there of considerable size. But almost im- 

 mediately upon entering it decreases in volume and after branch- 

 ing becomes connected with the neurites of the mushroom body 

 cells. The junction appears as complete as though there existed 

 here a veritable fusion. So fine are the fibers that the prepar- 

 ation also seems to show that the parallel fibers from the mush- 

 room body cells have branches in this place. The latter condi- 

 tion cannot, however, be the true one, for in all other prepara- 

 tions, which are numerous, no such branching is shown. With 

 Lenhossek ( 95) I agree that in general the bichromate of silver 



