CUTANEOUS SECRETIONS. 379 



whole skin ; they are racemose, branching glandules, with flask-like 

 or pear-shaped secreting vesicles (the saccules or acini) and a very 

 narrow neck. There are simply two anatomical points to which 

 we would here refer, seeing that they have a hearing on the further 

 consideration of the sebaceous matter. The first of these points 

 is, that these sebaceous glands are always entirely embedded in 

 the non-fatty corium, and, although they secrete fat, are never 

 found lying in the fatty subcutaneous areolar tissue ; the second 

 is, that the great majority of these glands are grouped around the 

 roots of the hairs, and that their narrow mouths open into the 

 hair-follicles ; it is only on the nymphce, the glans penis, and the 

 inner membrane of the praputium, that we find sebaceous glands 

 independently of the presence of hairs ; the glands on these parts 

 ha\e, however, a somewhat different formation, the acini or saccules 

 being more rounded and grouped in a mulberry-like form. We 

 might here also mention the racemose Meibomian glands, and the 

 coiled and twisted tubular ceruminous glands, since we shall, in 

 the present chapter, consider their secretions, in so far as our 

 chemical knowledge of them at present extends. 



Although the secretions of the above named glandular organs 

 by no means have a perfectly identical composition, and indeed 

 probably, to a certain extent, contain very heterogeneous con- 

 stituents, yet, in regard to many of their physical and chemical 

 relations, they are at least as nearly allied as the transudations 

 which were considered in a previous chapter. In order as 

 much as possible to include the comparative physiology of the 

 subject, we shall, at the same time, notice the composition of 

 castoreurn, which has been shown by E. H. Weber* to be 

 essentially nothing more than the secretion from the innumerable 

 preputial folds of the penis and clitoris of the beaver. 



In all these secretions, without a single exception, we find a 

 larger or smaller number of morphological elements: all these 

 glandular vesicles and ducts are invested with a fine cellular 

 epithelium, and hence, on a microscopic examination, we find 

 epithelial cells in all these secretions ; we often, however, find more 

 pavement epithelium from the external skin than delicate cellular 

 structure from the interior of the gland. 



In most of these secretions, and especially and invariably in 



those of the Meibomian and ceruminous glands, we find peculiar, 



oval, angular, or roundish cells, from T ^th to T ioth of a line in 



diameter, which, in addition to a pale nucleus with nucleoli, con- 



* Ber. d. k. sachs Gesellsch. d. Wiss. Bd. 2, S. 185200. 



