454 
DR. HEEBEET WATNEY ON THE MINUTE 
Virchow (22), 1853, noticed a white substance in the veins of the villi. He con- 
sidered the whole parenchyma of the villus to he full of fat during absorption. 
Virchow (23), 1857, noticed that the epithelial cells of the gall-bladder are filled with 
fat, the fat lying in parallel rows in the epithelial cells. 
Brucke (24), 1851 and (25) 1853, repeated and confirmed the researches of Lacauchie, 
and of Gruby and Belafond, concerning the contractility of the villi. Brooke further 
showed that that contractility is due to bands of longitudinal muscle-fibres running up 
to the points of the villi ; and, further, that these muscles are only processes from the 
muscularis mucosse*. This author supposed that each epithelial cell is open at its distal 
and proximal ends, that the fat encounters (at the entrance to the cells) a plug of 
mucous consistence, and that the central canal is not a vessel but only a space between 
the tissue. 
Bonders (12), 1853 and 1856, denied the existence of openings at the ends of the 
epithelial cells. He thought that the fat goes through the villus in a cloud-like form. 
Moleschott and Marfels (26), 1854, maintained Brucke’s opinion of the epithelial 
cells being open at their free extremities. They found that in frogs mammalian blood 
and in mammals pigment-granules penetrate the epithelium. 
Bonders, Wittich (27), and Hollander (28) obtained negative results on repeating 
the experiments of Moleschott and Marfels. 
Kolliker (29) spoke in the most positive terms of the epithelial cells being closed at 
their free extremities ; further, Kolliker and Funke (30), 1855, showed that the “basal 
border” of the epithelium is striated. Kolliker thought that the basal seam is 
penetrated by little pores through which the fat passes. 
Brettauer and Steinach (31), 1857, showed that the seam is sometimes composed of 
little rods. 
There was much discussion, which may be found in the literature of the subject, on 
the character of the seam, its thickness in fat-absorption, and the manner in which fat 
penetrated it ; and subsequently there was great dispute about the origin and signifi- 
cance of the goblet-cells. Neither of these questions will be entered upon in this paper. 
Todd and Bowman (32), 1856, described a basement membrane in the villi as a single 
layer of homogeneous membrane. 
This question of the existence of a basement membrane is nearly as important as 
the similar one of the occurrence of a membrane belonging to the chyle-vessels ; for if 
there be a membrane, the views of Heidenhain and all his followers must fall to the 
ground, unless we accept a basement membrane in the sense of Kolliker. The follow- 
ing authors assert that there is a basement membrane : — Goodsir (7), Bonders (12), 
Todd and Bowman (32), Eberth (33), Bonitz (14), Erdmann (34), and Bebove (35). 
Billroth (36), 1858, supposed that the epithelium of the frog’s intestine has an inti- 
mate connexion with the connective-tissue corpuscles. 
* The muscularis mucosse had been previously described by Middeldobef in a paper on Bbtjnnee’s glands 
( 1846 ). 
