STRUCTURE OP THE MUCOUS MEMBRANE. 
413 
agminatae of the same intestine. The first of these I have 
not examined ; the second, namely, the glandulae solitarise of 
the small intestine, particularly of the ileum, are, as I have 
already described, aborted villi surrounded by a zone of 
simple follicles, and not glands ; their whitish appearance, 
when contrasted with the neighbouring mucous membrane, 
being due to the less degree of vascularity of their area. The 
glandulae agminatae of Peyer, presently to be described, are 
not saccular glands ; nor are the solitary glands of the large 
intestine. 
Compound Glands . — The compound glands usually described 
are small lobulated glandular bodies, termed pharyngeal and 
oesophageal, in connection with the pharynx and oesophagus, 
and duodenal or Brunner’s glands in connexion with the 
duodenum. In structure they resemble salivary glands, 
being composed of acini, efferent ducts, and an excretory duct. 
These are all the compound glands generally recognized ; 
but I have now to call attention to another form of the com- 
pound gland more simple in structure and more superficial 
in position than those already mentioned, and approaching 
very closely in appearance and structure to the sebiparous 
glands of the skin ; they are very probably the true muci- 
parous glands of the alimentary canal. 
The muciparous glands are found both in the small and 
large intestine. In the latter they occupy the alveoli, and 
constitute the floor of those cavities. They are white, semi- 
transparent, obscurely lobulated, and provided with an ex- 
cretory aperture. In a word, they correspond so completely 
with the sebiparous glands of the skin that the analogy 
between them is forced on the mind in regarding them ; 
their whiteness and semi-transparency being due to their 
epithelial structure, as is the case with the sebiparous glands. 
Commonly each alveolus has its separate gland ; but occa- 
sionally, and especially when the alveolus is longer than 
usual, there may be two glands and two excretory apertures. 
The gland fills the alveolus, rising almost to the level of its 
brim, and thereby rendering the cavity of the alveolus very 
shallow ; and the excretory aperture is surrounded by a pro- 
tuberant lip. 
As 1 have before remarked, on those elevations of the 
mucous membrane of the large intestine constituting the 
solitary gland, the alveoli are deeper and smaller; so deep, 
in fact, that the floor is not seen : hence, probably, the sup- 
position generally entertained with regard to them, that they 
are a mere aggregation of simple follicles. 
The muciparous glands of the small intestine have hitherto 
xxviii. 53 
