THYREOID GLAND OF THE TELEOSTS 



741 



short axis. Baber observed in the conger eel folHcles of very 

 large size. 



Some follicles send out branches which widen near their end 

 to form secondary cavities, (pi. V, fig. 16). In the series from 

 which one section is figured, (pi. V, fig. 15), may be found a 

 large follicle sending out a branch, and further along two fol- 

 licles (F. /.) connected by a tube (D) of high cylindrical epithe- 

 lium. The tube represents the branch of the former section and 

 in another section both follicles are entirely separated. Going 

 further in the series the small follicle increases in size while the 

 large one sends out a second branch. Thus around a larger 

 follicle as a center may be grouped several smaller ones connect- 

 ing with the original follicle by 'ducts' as it were. These ducts 

 might be compared with the intercalary portions of other glands. 

 Baber likewise observed branching follicles in the conger eel. 

 Baber claims that new follicles arise from groups of cells some- 

 what rounded in form and situated in the epithelial wall of the 

 larger ones. I was unable to observe such processes. Lymphatics 

 are present in the thyreoid gland of the eel, although Baber denies 

 their existence. 



Baber records the follicular epithelial cells as highly columnar 

 in form. I find cuboidal epithelial cells measuring from 10 to 

 15m high. 





Fig. 2. Sections through the thyreoid gland of Clupea. A, in the aortic bifur- 

 cation; B, between the first and second branchial arteries. 



JOURNAL OF MORPHOLOGY, VOL. 21, NO. 4. 



