260 FRANK E. BEDDARD. 
of the calciferous glands, must indicate a change in func- 
tion. | 
In the present state of our knowledge, we can do no more 
than guess what this change of function can be. We are 
helped, however, by certain facts in the histology of the glands, 
and by the analogies offered in other animals. The structural 
change undergone by the calciferous glands is a reduction of 
the lumen, and presumably, therefore, a rapidly decreasing 
amount of secretion furnished to the csophagus. I have 
never, it should be mentioned, seen the least trace of any cal- 
careous particles in the calciferous glands in either Gordio- 
drilus, Stuhlmannia, Notykus, or Eudriloides. As the 
secreting tissues diminish, the tissues surrounding the glands 
increase in amount and in specialisation. They are supplied 
with blood from a large vessel which is dilated within the 
gland, and by its devious course must prolong the time that 
the blood is submitted to the action of the surrounding cells. 
The function of these glands must, I believe, have some rela- 
tion to the blood. I regard them as analogous to the spleen 
of the Vertebrata; and in relation to this matter it may be 
pointed out that it has been stated that the spleen is originally 
formed as a diverticulum of the gut, thus indicating a conver- 
sion from a gland appended to the alimentary tract, and pro- 
bably performing the function of a digestive gland to a “‘gland” 
concerned in some way with the blood. The instances de- 
scribed in the present paper are remarkably analogous. A 
series of glands undoubtedly related to the function of diges- 
tion are metamorphosed into glands which also appear to have 
some relation to the vascular system. In the family Enchy- 
treide there is something of the same kind. The genera 
Buchholzia and Henlea are furnished with glandular ap- 
pendages to the cesophagus, which can hardly be different in 
their nature from the calciferous glands of earthworms ; from 
these glands (in most cases) the dorsal vessel arises. In the 
genus Mesenchytrus there are no such glands, but the 
dorsal vessel at its origin from the pericesophageal plexus (or 
sinus) contains a cellular rod which has been called the “cardiae 
