68 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 
peduncle, where also a small tract is found under the endoderm. 
(See preceding head, or Claus*®, and Conant*’). As already noted, 
under the distal complex eye, I find only large nuclei to represent 
the ganglion cells. By saying this, however, I do not wish to dispute 
their ganglionic nature. The large multipolar ganglion cells I have 
noted under the preceding topic. 
The Supporting Lamella.—The supporting lamella is a continua- 
tion, through the peduncle, of the jelly of the bell. It completely 
surrounds the ampulla and the lithocyst, and also forms a partition 
between them, so that, as already noted, the lithocyst becomes 
completely surrounded by it. It also sends a_ partition ventrally 
between the complex eyes (Figs. 7, 13). Its thickening to form a 
support for the lens of the proximal complex eye has already been 
noticed. [I shall limit myself in the discussion of the supporting 
lamella to the above short resume, since Schewiakoff gives further 
detail. 
The Endothelium of the Ampulla and the “ Floating Cells.’—The 
ampulla is lined by a secreting epithelium. This is shown by the 
large masses of a secretion within the bases of the cells, and by 
smaller masses scattered in the central and more distal parts 
(Figs. 7, and 27, lower half). The section of the cells is such in Fig. 
7, that the bases of some (those nearest the supporting lamella) are 
taken, the central nuclear region of others, and the tips of those 
farthest from the supporting lamella. The section may be said to be 
taken diagonally through the bases and central parts of some of the 
cells, but owing to the curvature of the ampulla wall, through the 
tips of others. The secretion is a colloid substance, staining yellowish 
gray with iron-hematoxylin, blue with Lyons blue, and reddish 
with borax-carmine. Sometimes darkly staining rods and fibers of 
unknown origin could be seen within the larger masses of the 
secretion (Fig. 7). These rods and fibers could also be seen in 
spaces within the cells, from which the secretion had evidently been 
dissolved. I think there can be no question but that the masses 
described are a secretion. Many series, however, do not show it; 
indeed, an examination of Conant’s slides gave me little evidence 
of a secreting function, though I could demonstrate it in his sections 
both within the endothehum and also the floating bodies. The 
