480 REPORT OF THE HARVARD AFRICAN EXPEDITION 
The critical point that remains upon which the specific diagnosis of our speci- 
mens must be made rests in the size of the spicules. In S. armatus the left spicule 
length is given as from 4 mm. to 4.25 mm.; in S. pigmentatus the length of this 
spicule is stated as 6.5 mm. to 6.7 mm. 
In our material cleared both in glycerine and in lactophenol, the caudal ex- 
tremities of the specimens are rendered very transparent making details of the 
caudal papillae, etc., readily visible, but, because of the longitudinal markings 
of the cuticle and the thickness of the body wall, the fine spicules (10u wide) 
and gubernaculum are either entirely obscured or, if visible, are so disposed that 
accurate measurements, such as are essential if they are to be used as a basis for 
species differentiation, cannot be secured. In two of the more favorable speci- 
mens in which both ends of the left spicule were clearly visible, measurements 
made as carefully as possible gave lengths of 4.2 and 5.0 mm. This would tend 
to throw the identification of the parasites into Ortlepp’s species S. intermedius, 
but for the reasons given above it does not seem satisfactory to me to make the 
size of the spicules the sole basis for species differentiation. From general 
considerations of the specific points discussed above, I believe that the worm 
from Cercopithecus diana diana coincides more closely with the description of 
Streptopharagus pigmentatus than it does with S. armatus, and I would there- 
fore assign the material under this name. 
Cylicospirura subaequalis (Molin, 1860) Vevers, 1922 
Four specimens, all mature females, killed in formalin, were available for 
study. Three of these specimens were more or less unbroken; the fourth was 
cut off in the caudal region of the body. The body is strongly coiled posteriorly. 
The only specimen that could be satisfactorily straightened measured about 
24 mm. in total length. The maximum breadth is 0.56 mm. The cuticle is 
finely striated. The anterior extremity tapers to a truncated extremity (No. 399, 
Fig. 1). The oral aperture is hexagonal in shape. The buccal cavity (No. 399, 
Fig. 2), lined by a thick wall of chitin, is funnel-shaped, with an anterior conical 
portion, 160u wide at the rim, and a stem-like posterior portion, or pharynx, which 
opens into the oesophagus. The depth of the buccal cavity is about 145u. There 
are six cuticularized plates more or less triangular in shape, disposed radially 
in the buccal cavity. The apices of these plates or ‘‘teeth”’ are bifid, and, in 
some specimens, project slightly beyond the rim of the oral aperture. There are 
three pairs of cephalic papillae: — a lateral pair (amphids) and two pairs sub- 
median in position. ‘The oesophagus, from 2.4 mm. to 2.96 mm. in total length, 
consists of the usual, short, glandular part surrounded by a nerve ring 0.35 mm. 
from the anterior extremity of the body and a longer muscular portion. Neither 
cervical papillae nor the position of the excretory pore was visible. The tail of 
the female is bluntly rounded and short, the anus being from 170 to 250u 
from the posterior extremity. ‘The vulva varies in position. In the specimen 
with the shortest oesophagus (2.4 mm.) it is situated behind the end of the 
oesophagus, 4.16 mm. from the oral extremity of the body. In the remaining 
three specimens the vulva lies anterior to the end of the oesophagus, and is not 
