STUDIES ON THE TURBELLARIA. 4.61 
The fully-formed egg is ‘25 mm. in greatest diameter. It 
is not spherical, but more nearly of the form of a hemisphere, 
with one side strongly convex and the other flat. It is enclosed 
in a hard, opaque, chitinous shell. 
After being formed the egg does not appear to remain very 
long in the uterus, but soon drops out to lie among the mud. 
A good many were picked out of the sediment at the bottom 
of the vessel, and were treated with a solution recommended 
by Hemming for softening chitin, but I was disappointed to 
find that, though some of them had been kept in water for 
days after being laid, none of those of which successful sec- 
tions were made had developed, each containing the unaltered 
oosperm (in one or two cases two) with its enclosing mass of 
vitelline matter. 
Affinities.—The combination of characters with which 
Anomalocelus presents us places it outside the limits of 
all the known families of the Rhabdoccela. ‘The arrangement 
of the male ducts (with the vesicula seminalis and prostate- 
reservoir both enclosed in the penis-sheath) is a very excep- 
tional one, occurring among previously-known forms only in 
the Vorticida, from all of which the new form is dis- 
tinguished (1) by having diffuse or follicular testes, and (2) 
by having a pharynx rosulatus instead of a pharynx 
doliiformis. 
‘The possession of follicular testes is also a somewhat 
exceptional character, occurring only in the Alloioccla 
and in the genera Mecynostoma and Alaurina, with none 
of which Anomaloccelus has any close alliance in other 
respects. 
Von Graff (14, p. 217) enumerates those genera in which 
the ovary is single. Of these Prorhynchus, Microstoma, 
and Anoplodium may be at once left out of account as 
widely differing from the new form in many respects. We 
may also rule out, as manifestly not nearly related, Omalo- 
stoma, with its pharynx simplex and two reproductive 
apertures, Byrsophlebs, which has compact rounded testes 
and two reproductive apertures, Mesostoma and Castrada, 
