50 CALIFORNIA ACADEMY OF SCIENCES. 
fiz. 50)., the section is made through the junction of the nephridio-vesicle and the 
collar, and the ganglion (x. g/.) below is small, not yet branched. In fig. 50c, the 
section is made close to the pore where the ganglion (x. g/.) is branched. These 
branches always extend towards the collar, never the other way. Both these sections 
from which the drawings were made are not quite in right angle to the longitudinal 
muscular layer, but slightly slanting. 
The nephridio-stome is rather large, but very transparent and quite difficult to 
detect. It is flat, rosette-like and placed half-way between sete 1 and 2. The duet 
descending from it is remarkably thin, straight and never winding. ‘The nephridio- 
stome is normally situated, piercing the anterior septum as usual. There is no central 
cell and nucleus larger than the other, but seyeral smaller cell nuclei are visible in 
the center below the large marginal cells, which are about 16 to 18 in number and as 
usual placed in a crescent. Between these cells and the real margin of the lip there 
is a row of smaller cells and nuelei, the latter being slightly lower than the inner 
large nuclei, but sufficiently situated in the same plane to be seen at the same time. 
7Zestes consist of two pairs of small bodies, as usually situated in somites x and 
xi, attached to the septum close to the body-wall in the anterior part of the somite. 
They are deeply lobed and the lobes are very narrow, parallel and generally three or 
four in number. The testes are free, not enclosed in the sperm-sacs. 
Sperm-sacs (figs. 5 and 6). There are two pair of sperm-sacs, one pair in 
somite xiand one pair in xii, attached to the anterior septum in the somite, rather 
high up, but below the cesophagus. The four sperm-sacs are of about the same size, 
comparatively small, and deeply lobed very much like the posterior sperm-sac in 
Ocnerodrilus Beddardi, ete., none of the lobes being very much larger than the other. 
It must be remarked that the sperm-sacs are not situated in the same somites as the 
testes, somite X possessing testes, but mo sperm-sacs, and somite X11 possessing sperm- 
sacs, but no testes. The respective sperm-sacs are not connected with each other and 
there is no median sperm pouch. The trabecula or muscular divisions of the sperm-sacs 
are numerous and the chambers enclosed by them are comparatively small. 
os.7,8, 11). There are two pair of ciliated rosettes, 
oD > 
one in xiand one in xii,as usual. They are very large and folded, deeply crumpled and 
very prominent, occupying about + of the somite. The funnels are wide, with a 
Spermducts and rosettes (fi 
slight posterior swelling. The spermducts run backward and sideways, connect in 
xii, and continue to somite xvii, where they leave the body-wall, ascend slightly and 
connect into one single duct, which opens out jointly with the prostate, in the 
posterior part of the somite. The duct does not enter the prostate, but both open 
jointly in one slit, running parallel to the intersegmental furrow. The spermduct is 
throughout of the same size, only widening out just previous to entering the rosette. 
The lower descending part of the duct, between the spermiducal pore and the bend 
where it starts forward, is slightly narrower than the anterior part. 
