280 
H. L. M. PlXEl.L. 
I 
occur in a completely developed specimen. On tlie anal side 
it turns inwards, following the curve of the lopbophore, and 
is connected from side to side just in front of the anal papilla 
by a large ganglionic mass (Fig. 8, g.). From this passes down- 
warils on the left side the conspicuous nerve-cord. In tlie 
nephridial region it is separated from the epithelium, and is 
embedded in the basement tissue (Fig. 14, /. n.). After passia^>- 
internally to the nephridial duct [n. d.) it turns outwards and 
i-ejoins the epitlieliurn a little to the oral side of the left 
lateral mesentery. From here it extends nearly to the 
ampulla as a very conspicuous cord in contact with the 
epitheliiun, but protruding- slightly into the basement mem- 
brane (Fig. 13 /. ?/.). The centre is occupied by a cleat- 
substance which stains only slightly and around this are the 
nerve-cells. 
Alimentary Canal. — In the stomach the ciliated groove 
with deeply chromatic nuclei is much smaller and less notice- 
able than in Ph. v;incou verensis. The distal part of the 
iiitesrine is imirkedlv triano-ular in section and lined with 
• O 
suiiill cubical cells (Fig. 13, int.), the short termimd rectum 
having columnar cells (Fig. 1 1, r.) ; the coelom is divided into 
its nsuiil four compartments even in the ampulla, as far as the 
bend in the digestive tube. 
Vascular System. — The corpuscles are but very slightly 
larger than in P h. v an co u ver en si s, being on an average 
10-12 p in diameter, and the same remarks as to staining, etc., 
apply to them. 
The coeca frequently branch, which they have never been 
seen to do in Ph. va nco u v e r ens i s. 
Excretory System. — The excretory tubes have the usual 
position, but differ slightly from those hitherto described. 
Each has a large funnel ojiening into the anterior coelom and 
a. smaller one higher up opening into the posterior coelom ; 
neither of these has its wall prolonged downwards for any 
distance as is usually the case. In addition to these funnels 
there is a, wide orifice for communication between the anterior 
and posterior coclomic spaces owing to the lateral mesenteries 
