E. C. Faust 
251 
Cercaria nervosa nov. spec. 
(Plate XXI, Fig. 2 .) 
This amphistome larva, for which the name Cercaria nervosa is proposed. 
was found producing a heavy infection in Planorbis mollendorfi Cless., secured 
from a small stream in a temple ground in the Western Hills, some 35 miles 
from Peking. 
The larva is pyriform, with a long narrow tail which has a jerky, nervous 
movement. The body measures 0-15 x 0-13 mm., while the tail averages about 
0-3 mm. in length by 25 ^ in width. The entire body is covered with minute 
spines and, in addition, the head is beset with three rows of more conspicuous 
spines. A pair of pigmented eye-spots are found just posterior to the oral 
sucker. 
Ihe oral sucker has a small opening but a heavy muscular bulbus. At its 
inner limits definite pharyngeal pouches (pp) are seen. The greatest diameter 
of the organ is 33 p. From the mid-region of the oral sucker there leads inward 
a narrow prepharynx, lined with a mucoid thickening in the middle third 
and surrounded by a minute muscular pharynx in the distal third. The caeca 
arise directly from the pharynx and extend as a broad arch in a latero-posterior 
direction. 
The posterior sucker measures 40 x 80/x, the transverse diameter being 
the greater. The excretory system consists of a small muscular bladder ( 6 ), 
with a posterior pore; collecting tubules in the body which arise from the 
anterior mid-lme of the bladder, and by characteristic coiling proceed anteriad 
and then return to the posterior part of the worm; and a caudal element ex¬ 
tending to the distal region of the tail and there forking abruptly (see Fig.). 
Granules are found only in the middle part of the collecting tubule of the body. 
On account of the abundant supply of cystogenous granules throughout the 
entire body, details of flame-cell structure have not been observed. Three or 
four germ cell masses have been seen in the mid-region of the body. 
The parthemta is a simple sacculate redia without feet, but having a definite 
pharynx and a small rhabdocoel gut. 
Cercaria syhinoicadda nov. spec. 
(Plate XXI, Fig. 3.) 
The cystophorous cercaria, for which I propose the name Cercaria syringi- 
cauda, was found producing a very heavy infection in two collections of 
Melania ebemna Brot., taken from the backwaters of the Yantze valley at 
Kiukiang. At the period when the collections were made this host species was 
the only common mollusc in the area. 
6 . syringicauda has an oval body measuring sensu stricto 0-13 mm. lorn* 
bv 0-09 mm. wide. The main caudal appendage has a pyriform bulbous region 
immediately behind the body and an extremely long tube continuing distad. 
he bulbus has measurements about one and one-half times those of the body, 
