244 On ilie Structure and Developnent of 
wliicli is especially prone to take up fat and be converted into a 
fat-corpuscle. 
These corpuscles have recently been noticed in most of the 
connective substances, but it seems uncertain whether they are 
undergoing fatty change as a physiological or pathological act. 
They are said to occur constantly in the skin disease known as 
zanthelasma, and I have found them frequently in diphtheritic 
membranes, where they appeared to represent the corpuscles of the 
imperfectly developed tissue of the membrane, on the third or 
fourth day of the disease. 
7. Intermuscular Tissue.— \t has been claimed by some that 
there is a form of spindle cell in the intermuscular tissue in the 
thigh of the frog. This, however, is apparent rather than real. We 
find broad plates which are oval flattened bodies placed at certain 
distances apart (Fig. 8, Plate CLIX.). These seen in profile appear 
spindle-shaped. There is something peculiar about these bodies, 
for they seem to bear a close relationship to the elastic networks (a), 
so that in some cases it appears as if the flattened central bodies 
were directly connected with the elastic fibres as stated by Boll.* 
In many instances these elastic fibres lie upon the plates (b). The 
broad plates rest in a homogeneous, intermediate, and apparently 
structureless substance. In this tissue, therefore, it has not as 
yet appeared that there are fibrils in the intercellular substance. 
On the contrary, this substance is soft and homogeDeous and 
highly elastic, and gives the appearance of a tissue that has retained 
to a great extent its embryonic form. 
Connective Tissue of the Kidney (Fig. 9, Plate CLX.). — Here 
also the plate-like corpuscles may be seen {a) as distinguished from 
the lymphoid corpuscles (h), though the exact nature of the inter- 
cellular substance, whether fibrillary or not, is difiicult to determine 
with satisfaction. A normal kidney thoroughly injected through 
both vein and artery was employed in order to differentiate com- 
pletely the vessels, with the corpuscles in their coats, from the 
sustentacular tissue or supporting substance proper. 
8. Corneal Tissue. — There has been a great deal of discussion 
within the past few years as to the structure of the cornea, and the 
views of observers have differed according as they have confined 
their attention to the interiamellar spaces or to the bodies in them. 
The term corneal corpuscles, strange as it may appear, is even now 
used of the spaces by some of the best-known writers, and it seems 
evident that there is still doubt as to whether any real corpuscles 
exist or not. Eecently, this subject has been restudied by Wal- 
deyer, and we have been able to verify his conclusions in a very 
great measure, both as to the character of the corpuscles and the 
spaces in which they lie. These bodies appear, as stated by Wal- 
* ' Arch, fiir inikiosk, Aiuit.' 1870, 
