172 Journal of Comparative Neurology. 



behind the inner root of the mushroom bodies (providing one 

 may judge from the appearance of the fiber and the direction 

 of its branches). Just behind the inner root and to one side of 

 the base of the central body it becomes very much enlarged, 

 gives off two relatively short branches and then one long one 

 that passes up over the inner root and over the anterior root 

 just in front of the junction of the two with the stalks, as shown 

 by the dotted lines in the figure. Another branch a little fur- 

 ther forward passes up to and branches in the fibrillar region to 

 one side of the central body, while in front of this a number of 

 short branches are given off that branch very profusely in the 

 region to one side of the base of the central body. The main 

 fiber continues forward to the neighborhood of the antennal 

 lobes giving evidence of further branching, but on account of 

 being either unimpregnated or cut off can not be traced farther. 



The fiber shown in figure 35 is nearer the median plane 

 and appears to come from the oesophageal commissure, passing 

 upward and then directly forward under the central body, giv- 

 ing off along its course several branches that run back into or 

 towards the commissure and then four very long though small 

 branches that pass upwards in front of the central body ending, 

 so far as can be traced, above the level of the top of the latter. 

 One of the four passes farther forward and gives off a branch 

 that turns back into the neighboring region to one side. 



In figure 33 a more peculiarly twisted fiber (35) is shown, 

 which was found in the lateral region of the proto-cerebron be- 

 low and to one side of the anterior root and behind the opdc 

 body, near which it may pos.sibly originate. Its base is 

 at the right of the figure. It passes outwards for a short dis- 

 tance then backwaids, gives off a branch that turns upon itself, 

 divides again several times, some of the branches going up- 

 wards, the rest downwards and forward. There it passes down- 

 ward for a short distance and divides into two large branches of 

 almost equal size, one going backward, so far as traceable, ap- 

 parently to the posterior region of the brain, the other forward, 

 twisting above the parent stem and finally breaking up into a 

 number of branches that terminate behind the central body. 



