244 Prof. L. C. Miall on Dicranota ; 
calyciform cells of authors,* but I have been unable to 
ascertain what becomes of them, or to throw light upon 
their function. 
A striated seam now and then appears in fresh pre- 
parations, but does not occur in any of my sections. 
Larve containing food in the stomach often show 
extremely copious filamentous masses, apparently formed 
by a coagulable fluid secretion (fig. 17). The filaments 
may le side by side in long wavy bands, or may cohere 
into a dense mass enclosing fragments of food. Stronger 
filaments, apparently due to fusion of smaller ones, 
seem at times to issue from the sinuses of the folded 
epithelium. In some cases at least the epithelium shows 
a notable diminution of thickness when the filaments 
are abundant. Ihave not found the transparent vesicles 
abundant in any section which shows a plentiful fila- 
mentous substance. On the whole I am inclined to 
believe that the filaments originate in the salivary glands, 
and not in the stomach. 
Undeveloped nucleated cells can be found towards the 
base of the epithelium, and I have seen several of the 
stages of development figured by Balbiani.t 
The facts suggest that a digestive fluid is secreted by 
the cells, and accumulate in their interior as vesicles or 
drops; that it collects in the prominences upon the free 
ends of the cells; further, that during or after the period 
of discharge the cells contract and pass into a resting- 
stage. 
The facts (1) that the stomach is often completely 
emptied; (2) that the epithelium varies greatly according 
to the phase of secretion, indicate that the larva of 
Dicranota is well adapted for the study of the secretory 
changes which take place in a digestive epithelium. 
The origin of the filamentous masses is not perfectly 
cleared up. Certain facts, such as the apparent emer- 
gence of strands of filaments from the epithelial sinuses 
of the stomach, and the shrinkage of the epithelium when 
the filaments are abundant, have led me at times to 
suppose that they are secreted by the stomach. But the 
salivary glands contain a fluid which, when coagulated 
by alcohol, cannot be distinguished from the denser 
** Balbiani, loc. cit., p. 43, and authors there cited. 
+ Loe. cit., fig. 30. 
