376 
b.m. 
dell 
a eon 
The American Naturalist. [May, 
EXPLANATION OF PLATE. 
(DIAGRAMATIC.) 
Outer fibrillar connections in the outer fibrillar 
body 
Anterior optic tract.’ 
Antero-posterior optic tract. 
Antero-superior optic tract. 
Fibrillar connections in the outer lenticular 
mass of the middle body. 
Basement membrane of the retina. 
Fibrillar connections of the inner lenticular mass 
of the middle body. 
Fibrillar connections of the outer lenticular mass 
of the inner body. 
Dorso-cerebrum. 
Fibrillar connections of the inner lenticular mass 
of the inner body. 
Fibrillar bodies 1, 2 and 8, or outer, middle, and 
inner. 
Lower optic commissure. 
Posterior optic tracts. 
Postero-superior optic tract. 
Stalk of the outer mushroom body. 
Upper optic commissure. 
Supposed location of the cells of origin of the 
fibers of the a.—p.o.t. and ers o.t. 
The outer chiasma. 
The inner chiasma. 
? The tract to the optic body (op. b. ) 
