MR. E. C. BABER ON THE STRUCTURE OF THE THYROID GLAND. 
605 
Fig. 4. Transverse section of a portion of the wall of a large gland-vesicle from the 
thyroid gland of a Conger Eel, hardened in alcohol and stained with hsema- 
toxylin. (Obj. 6, oc. I., tube half drawn out.) 
i. Cavity of the large vesicle. 
2 , 2 . Its epithelial wall, of which the cells are represented semi-diagramatically. 
3 , 3 . Small vesicles, which are situate in the epithelial wall of the large vesicle 
and are separated by much flattened epithelial cells from the cavity of the 
latter. 
4, Another vesicle, separated by cells less flattened from the cavity of the 
large vesicle. 
5 , 5 . Vesicles distinctly outside the wall of the large vesicle, which appear to 
be growing outwards. 
The homogeneous contents of the small vesicles are seen with their jagged 
outlines. The vesicles represented in this drawing are not all quite on the 
same level. 
Fig. 5. From a section of the thyroid gland of the Tortoise, hardened in a 1 per 
cent, solution of chromic acid (17 hours) and subsequently in diluted and in 
strong alcohol, and stained with hsematoxylin. The intercellular reticulum 
is seen from the surface, but the intervening epithelial cells are not repre¬ 
sented. (Obj. F, oc. I.) 
Fig. 6. From a section of the thyroid gland of the Conger Eel, hardened in alcohol 
and stained with hsematoxylin, giving a surface view of the epithelial cells 
amongst which are seen the branched nuclei of the club-shaped cells. They 
are probably connected with the intercellular reticulum. (Obj. 6, oc. I., tube 
half drawn out.) 
Fig. 7. From a section of the thyroid gland of the Tortoise prepared as follows : 
injected by the method of puncture with -gth per cent, solution of osmic acid, 
hardened in a 1 per cent, solution of the same acid for five hours, and sub¬ 
sequently in alcohol, mounted in glycerine. It shows (at i) the epithelial 
wall of a vesicle cut obliquely, beyond which there projects (at 2 ) a membrane 
having delicate wavy strise on it. (Obj. F, oc. I.) 
Fig. 8. From a longitudinal section of the thyroid gland of a Kitten injected with 
nitrate of silver by the method of puncture, hardened in alcohol and stained 
with hsematoxylin. The drawing represents a portion of the wall of a vesicle 
seen from the surface. By focussing from the interior of the vesicle, three 
layers can be distinguished. First, the oval-shaped nuclei, at regular 
intervals, stained with hsematoxylin ; secondly, a layer of dots and short 
strise, stained with nitrate of silver, only represented in the centre of the 
drawing ; and thirdly, the outlines of the endothelial cells of a lymphatic, 
also stained with silver ( 1 , 1 ). (Obj. F, oc. II.) 
Fig. 9. From a section of the thyroid gland of the Tortoise (injected with Berlin 
