54 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 
extend to the lens as described. The prisms and pyramids are, 
further, the distal continuations of cells whose pigmented and 
nuclear parts lie in the so-called retina, but which, together with the 
vitreous body, I have named the retina proper. Conant has so sum- 
marily disposed of Schewiakoff’s distinction between retinal cells based 
on pigmentation and location of nuclei, that I need not say more. 
Schewiakoff’s Fig. 18 corresponds to my Fig. 1. In this figure he 
shows the vitreous body as homogeneous with pigmented areas 
(my long pigment cells) and with spaces with his visual rods. It is 
quite evident that his spaces with the visual rods correspond to 
my lighter areas with central dots; 7 e. my pyramids of the 
vitreous body are the same as the spaces shown in his Fig. 18. 
It is quite evident that Schewiakoff mistook the lighter areas for 
spaces. That they are not spaces can readily be seen by comparing 
them with real spaces. It is, of course, possible, too, that the reagents 
had dissolved the pyramids, leaving .only the axial fibers with a little 
pyramid substance about them, and that this is what Schewiakoff 
saw. I often found small circular spaces in the centers of the 
pyramid areas, as also in the prism areas (Fig. 3), which might be 
taken for hyaline visual rods, fibers, in transverse section, but in 
such spaces I could usually see a small dot to one side of the space 
that I take to be the rod (fiber) proper. Fig. 14 also shows such 
small circular spaces that have very much the semblance of hyaline 
rods. This figure is a transverse section of the vitreous body of the 
proximal complex eye, in which no long pigment cells or pyramid 
cells are present, but it serves well to illustrate the point. The above 
explanation also accounts for the large size of the visual rods (fibers) 
in Schewiakoff’s figures. That the fibers of the pyramid cells (visual 
rods of Schewiakoff) do not extend to the lens is quite evident in my 
Figs. 4 and 7. 
Again, since the long pigment cells are often not seen to termi- 
nate in a fiber, but a part of the fiber can often be seen in the 
distal part of the vitreous body and in the capsule, it will be quite 
readily seen how Schewiakoff should associate his visual rods, or 
fibers, with these distal parts of the fibers of the long pigment cells 
and suppose his visual rods to extend to the lens. 
Again, since the long pigment cells sometimes cannot be seen to 
terminate distally in a fiber, while the vitreous body at the same 
time may be broken away from the pigmented zone (Fig. 4), it is 
