ELEDONE. 5338 
G.). Hence the kidneys tend to diverge posteriorly. 
They are triangular in shape, the longest side being 
external. As they are wholly independent of one another, 
they differ from the kidneys of Sepza, where the two are 
in direct communication. The ureter is situated half way 
down the external side of the sac, and-bears the urinary 
aperture at the tip (fig. 37, Ur. p.). When fresh, the 
intestine, heart, liver, etc., may be seen through the 
transparent walls of the urinary sacs. On opening the 
kidney it is found to contain a thick colourless liquid in 
which may be seen yellowish accretions of guanin—both 
the liquid and the guanin being excretory products 
eliminated from the blood by the glandular cells of the 
kidney. Roundish colourless corpuscles are found floating 
in the kidney fluid, and also numbers of the small 
Mesozoan parasite, Dicyema miilleri, in various stages of 
development (Pl. X, fig. 81). Behind the kidney run the 
lateral venae cavae, and the two abdominal veins, and 
where these vessels touch the kidney wall they are 
produced into the club-shaped venous appendages. The 
kidney wall, which elsewhere is quite smooth, membranous 
and non-glandular, is composed of columnar glandular 
cells where it covers these appendages. As shown (PI. 
VII, fig. 56), these “ spongy bodies” have their surfaces 
furrowed by numerous folds and grooves, lined also by 
the glandular excretory epithelium of the kidney. The 
visceral mass dorsal to the kidney also protrudes into, 
and so encroaches on, the cavity of the sac. The ureters 
are canals about 12 mm. long, and are furrowed 
longitudinally on their inner surface. 
The Pericardial gland is a white gland of somewhat 
depressed oval form, situated on the inner anterior wall of 
the branchial heart, and enclosed in the pericardium 
(fig. 40, Br. app.). Numerous folds run inwards from the 
MM 
