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PROFESSOR J. STEPHENSON AND DR BAIN I PRASHAD ON 
channels which are such a prominent feature of this portion of the oesophagus on 
opening the narcotised or just killed worm. There can be no doubt, however, that 
the channels are represented by the spaces at the base of the lamellae, with which 
they correspond entirely in number and direction. 
Other Simple Forms of Glands. 
Of the same simple type, or only slightly more complicated, are the oesophageal 
swellings in a number of other Megascolecinae. Thus Bourne (4) describes in 
Megascolex cceruleus a series of swellings of the oesophagus occupying segments 
x-xv ; the inner wall is much plicated, raised into ridges and papillae, and exces- 
sively vascular ; smaller and larger concretions of calcium carbonate are usually to 
be found in this portion of the tube. 
Miss Raff has studied the alimentary canal in a number of Australian worms 
(20) ; she distinguishes simple swellings, sacculated swellings, and diverticula ; these 
'portions of the oesophagus have a folded internal lining ; the folds are very long and 
thin, and in the “ calcareous glands” they have a very large blood supply. Thus in 
Megascolex dorsalis the swelling is of the simple type ; in Fletcherodrilus the second 
stage occurs — there are lateral saccular swellings, but no duct separates them off 
from the central lumen. In Cryptodrilus saccarius (. Notoscolex saccarius) there 
are five pairs of glands, separated off from the oesophagus by a distinct duct, 
each bean-shaped, with a large vessel running along its length on the dorsal side ; 
microscopically, the very long folds, of the lining stretch right across the lumen 
and are richly supplied with blood ; the lining cells are ciliated, the cilia being visible 
with the low power. 
A simple form of gland is described by Benham in Plagiochceta punctata (3). 
The folds of the oesophageal lining, present in segments x-xiii, become more marked 
in segment xiv, where they give rise to calcareous glands. Each gland is a large sac 
at the side of the alimentary tube, but extending ventrally and dorsally so as almost 
to surround the tube along with its fellow. The whole region is very vascular. 
The Glands in the Genus Ocnerodrilus (Figs. 3, 4). 
In the genus Ocnerodrilus there are present in segment ix, below and at the 
sides of the alimentary tube, a pair of ovoid sacs opening ventro-laterally into the 
oesophagus towards the hinder part of the segment, and lying with their blind ends 
directed forwards. These have been described by Beddard in 0. eiseni (2), and by 
Eisen in 0. beddardi (9). Beddard found the lumen of the sacs divided up by a 
network of anastomosing folds of epithelium, the subdivision being more complete 
towards the blind end of the gland. “The epithelium of the gland appears to be 
everywhere ciliated, and the alimentary tract from the orifice of the glands becomes 
ciliated. The structure of the glands is much like that of the calciferous glands of 
