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PROFESSOR J. STEPHENSON AND DR BAINI PRASHAD ON 
show that the tissue of the glands is mesodermal and vascular in its origin ; later, 
he modifies this so far as to say “it is very difficult to state precisely from which 
embryonic layer the organs are formed.” 
That the view of the mesodermal origin of the glandular epithelium has gained 
some adherents is shown by the foliowing quotation from a recent elementary 
textbook : “ These glands are not true glandular diverticula of the oesophagus, but 
are mesodermal in origin and are merely the walls of the blood-vessels.” Since 
we believe this view to be entirely erroneous, and since one or other species of 
earthworm is a universally adopted subject of study in all elementary courses of 
zoology, it seems advisable to combat it, and to advocate a return to the, as we 
believe, correcter and simpler conception of the older authors. 
We imagine that the mistakes of the writers we have mentioned arise in part 
from their having confined their studies to the Lumbricidse, in which group the 
glands reach the highest degree of complexity. What we attempt in the present 
communication is therefore, firstly, to give an account of the simpler conditions 
met with in several forms which we have ourselves investigated, with a few notes 
on forms described by other authors. Secondly, to describe the glands, including 
their histological structure, in the common Indian genus Eutyphoeus, in which they 
have not so far been the subject of investigation ; the glands here are of a peculiar 
type, which is both interesting in itself, and capable of throwing light on the 
morphology of these organs in general. Thirdly, we deal with the Lumbricidse ; 
the condition in them is described at -some length, because the earlier descriptions 
are short and, from a modern standpoint, inadequate ; while the later, besides being, 
as we have already said, permeated by false morphological views, are, as regards 
their purely descriptive part, not at all easy to follow ; a lucid account, giving even 
a moderate amount of detail, of the glands of the common Lumbricidse does not 
exist. From these descriptions, and the considerations which attach to them, it will 
appear, we believe, that the glands are throughout the series what Beddard and 
the earlier authors always supposed them to be — foldings, which attain varying 
degrees of complexity, of the epithelial lining of the oesophagus. 
The literature of the subject is very large r and may be divided under four heads : — 
(1) Descriptions of the calciferous glands, from the morphological point of view, 
in a considerable number of worms. 
(2) Descriptions of structures' which may be homologous, or of a similar nature, 
though they differ considerably from the organs generally known as calciferous glands ; 
such are the diverticula from the anterior part of the gut in the genus Henlea 
(Enchytrseidse), certain structures in Buchholzia (Enchytrseidse) and in Limnodriloides 
winchelmanni (Tubificidse ; Michaelsen, 18), the so-called Chylustaschen in certain 
genera of Ocnerodrilinse, and the unpaired diverticula of Eudriloides and Stuhl- 
mannia (Eudrilinse). 
