200 
the capsular layer (or walls of the cartilage cavities). Each 
column or row of cartilage cells thus formed corresponds and 
is found to be placed opposite to one of the growing processes 
of the medullary tissue, and the liquefaction of all the cartilage 
substance, except the cells, precedes and gives room for the 
growth of this offshoot of medullary substance. The cartilage 
cells are not, however (as has been generally supposed), simply 
displaced by the growing cells of the medulla, but they them- 
selves undergo proliferation, and become converted into 
masses of nucleated protoplasm, which ultimately become 
medullary cells. A certain number of the latter are accordingly 
lineal descendants of the original cartilage cells. This parent- 
age involves the transformation (or retransformation) of the 
substance of the cartilage cell into the protoplasmatic sub- 
stance of the medullary or lymphoid cells, which, if expressed 
in Beale’s terminology, is a metamorphosis of ‘‘ formed matter” 
back again into unformed or “‘ germinal matter.”’, No ground 
was seen for supposing an endogenous or independent for- 
mation of blood-cells in the medulla. 
Glands of the Stomach— Two important memoirs have 
appeared on this subject; one by Heidenhain on the peptic 
glands; another by Ebstein on the so-called mucous glands 
of the stomach (Schultze’s ‘ Archiv,’ vi, p. 368, and ibid., 
p- 515, 1870). In both sets of researches the stomachs of 
dogs were used, and specimens were taken at different times 
from animals both fasting and during digestion. The stomach 
was hardened in alcohol, and the sections tinted with carmine 
or aniline blue, the latter reagent being very useful in tinting 
different structures unequally. The peptic glands are either 
single or—frequently in the dog, more rarely in man—com- 
pound ; but in most respects these varieties agree. According 
to Heidenhain, three parts may be distinguished in each— 
the orifice which is lined with cylindrical epithelium like that 
of the mucous surface ; the contracted neck of the follicle ; 
and the dilated body of the gland or follicle itself. In the 
compound glands the arrangement may be compared to the 
hand and fingers of a glove. In the follicles themselves, 
which are usually spoken of as containing the peptic cells, 
two forms of cells may be traced—the prominent, large, ex- 
ternal-cells, which H. calls “ tnvesting” cells (Belegzellen), 
apparently the “ peptic cells”’ of authors ; and certain smaller, 
pale, and less conspicuous cells, situated internally, apparently 
unnoticed before, which he believes to be the true agents in 
secreting pepsin, and therefore calls the “capital” cells 
(Hauptzellen). These two varieties differ in their behaviour 
with reagents, but especially so when examined during 
