PHARYNGEAL GLAND OF THE EARTHWORM 49 
dilated terminal portion of these fibrils ; he also disagreed with 
Smirnow as to their tubular structure and he described them 
once more in some detail. These fibrils in traversing the 
pharyngeal epithelium do not ramify and are completely 
devoid of the varicose nodules so characteristic of the nerve 
fibrils which are met with in the same pharyngeal epithelium. 
He failed again to detect the origin of these fibrils and still con- 
sidered them to be nervous elements, but he added that further 
study, and especially the discovery of their central origin, 
would finally solve the problem as to their nature and their 
function. 
The same year Langdon (1895), relymg upon Smirnow’s 
description, denied the nervous nature of the clubbed fibrils and 
considered them to be glandular or mucous cells. 
More recently, Dechant (1906) demonstrated the same fibrils 
by a metallic impregnation method, and, in accordance with 
Retzius, described them as nervous elements. 
I myself have recognized the structures described as clubbed 
fibrils by Retzius in the pharyngeal epithelium of Lumbricus 
sp. fixed with Champy and stamed with Iron Haematoxylin. 
The fibrils, in enormous numbers, run between the pharyngeal 
cells and are either straight or sinuous ; they all terminate in a 
very dilated portion filled with granular substance (Text-fig. 5, 
A and B). 
The merest glance at the structures convinced me that I was 
dealing with the same mucin ductules and their discharge 
pockets. The only difference between these structures and 
those previously described consists mainly in the fact that, 
while previously we stained only the mucin which fills the 
ductules and the pockets, now we stained the ductules and the 
pockets themselves. Moreover, the figures of the clubbed fibrils 
as shown in the papers of Retzius, Smirnow, and Dechant are 
similar in all respects to my figures of the intra-epithelial mucin 
ductules and their discharge pockets (Pl. 3, figs. 3, 7, and 8, 
and Text-figs. 4and 5). On the other hand, the fact that these 
authors succeeded in detecting these salivary ductules by 
metallic impregnation methods is not surprising, as these 
NO. 257 B 
