296 The Brain of the Locust. [ April, 
under a power of 725 diameters, with masses of granules among 
the fibers which are much finer than in the optic or antennal lobes. 
At the point passed through by section 17 the trabecule appear 
to have no connection with the stalk, but the latter appear to stop 
abruptly just before reaching it, the envelope of ganglionic cells 
and fibers surrounding the trabecule being interposed between 
the base of the stalk and the trabecula. (This does not preclude 
the fact that the stalk does not arise from the trabecula, though 
there are no signs of it in this section; for it clearly appears to 
thus arise in the drawings and descriptions of Dietl, Flogel, and 
Newton.) 
The structure of the trabeculz in the locust, judging from our 
sections, appears to be more complex than would be inferred from 
the observations of the other anatomists just mentioned. Section 
17 (Pl. 11, Fig. 2, trad.) passes through the middle of each of 
these bodies, and it then appears that there are four bundles of 
nerve-fibers passing out of each body. A bundle of transverse 
nerve-fibers (Fig. 2, 4c. 2. and Fig. 3) passes along under the 
central body, directly through the middle of the trabeculz, and 
anastomoses with the fibrous envelope of each trabecula. In front 
of this transverse intra-trabecular nerve is a small short ascending 
bundle of fibers (Fig. 3 a. ¢. 2.) which passes next to the pedicel, 
but does not apparently form a part of it, but anastomoses with 
the fibers on each side of the central body. Below, the fibers 
pass downward and outward to apparently connect with the 
fibrous envelope of the trabecula. Another short bundle passes 
out from the trabecula obliquely towards the central body and 
anastomoses with the fibrous envelope of the central body. 
Below, but in the same plane, is another transverse bundle of 
fibers (Fig. 3,2. ¢. #.), which is slightly curved and on the left side 
its fibers are distinctly seen to enter the trabecula. This lower in- 
trabecular nerve, as we may call it, connects with three vertical 
short nerves arising from near the edge of the lower furrow between 
the hemispheres of the brain. Of these, the central one (centr. 2.) 
is in the median line of the brain, and the lateral ones (/a¢. 7.) are 
on each side. There would thus seem to be a direct double nerv- 
ous communication between the two trabeculae, and with the- 
fibers surrounding the central body, and hence with the rest of 
the brain. This seems to be opposed to the statement of Newton 
that the trabeculz, and the mushroom bodies in general, have no 
