476 
PROFESSOR J. STEPHENSON AND DR BAINI PRASHAD ON 
half their height ; and there thus extends for some distance a series of ridges, 
coexistent with and internal to the series of tunnels, the ridges representing the 
central halves of the lamellae and the tunnels being situated between their 
peripheral portions. 
The epithelium of the pouches resembles that of the oesophageal tube ; on the 
surface of the cells in both situations is a fine, completely colourless and non- 
staining border. 
Towards the hinder end of segment x the epithelium of the tunnels changes its 
character ; it becomes cubical, and shows a number of hair-like tags, which soon 
appear as definite long cilia. In some places the surface of the epithelium is 
merely shreddy. The tunnels begin to elongate ; they may now be 18 in number 
in each pouch. 
The anterior part of the dilatation in segment xi bulges forwards so as to 
overlap the hinder part of the sac in x, and therefore both are cut in a number 
of sections (text-fig. l). 
The lateral dilatations in segment xi show about 35 tunnels on each side, 
including those which are incompletely divided by lamellae which, springing 
from the periphery, do not reach the oesophageal lining. The mid-ventral lining 
is free from tunnels. The tunnels are in general much elongated in a radial 
direction. The cells clothing the lamellae are in these specimens entirely dis- 
integrated, and have thrown off very numerous globular granules which stain 
deeply with haematoxylin. The fine structureless border of the oesophageal epi- 
thelium changes into an irregular layer of rodlets in the hinder part of 
segment xi. 
