38 ELEMENTARY HISTOLOGY. 
b. Compound glands. In compound glands each depression 
instead of being a simple pit is itself subdivided or 
branched, often in a very complicated manner. There 
are two chief varieties: (1) tubular glands, in which 
the several sub-divisions are tubular, and of tolerably 
uniform diameter throughout : and (2) racemose glands, 
in which the ends of the pits are dilated into globular 
chambers or alveoli, to which the special glandular 
epithelium is usually confined. 
Compound tubular glands. Take prepared section of 
kidney of frog: mount in balsam, and examine with 
both low and high powers. Note :— 
i. The tubular gland-cavities, cut at various angles. 
If cut transversely a tube will appear as a 
circular ring: if cut obliquely as a more or less 
elongated elliptical ring: if cut longitudinally — 
as two parallel rows of epithelial cells. 
iii The characters of the gland cells; a single layer 
_ of cubical granular cells. ' 
iii, The Malpighian bodies: spherical dilatations on 
the tubes, into which project little knots of 
capillary bloodvessels. Their structure is most 
readily made out in specimens in which the 
bloodvessels have been injected with a coloured 
substance to make them more distinct. 
c. Glands of stomach. 
The glands of the stomach are well adapted for a more 
minute examination of the histology of glands. 
Examine again with a high power the section of cardiac end of 
dog’s stomach already used for columnar epithelium : note :-— 
1. Characters of the glands: tubular glands, either simple 
or very slightly branched. 
2. Characters of the gland cells: three distinct kinds of 
cells. 
i. Columnar cells: arranged in a somewhat radiate 
manner round the mouths of the glands. 
ii, Cubic cells: or peptic cells: lining the deeper parts 
of the glands: cubical granular cells with cen- 
trally placed nuclei. 
