E. C. Faust 263 
within the body is a pair of lateral suctorial pockets (Isp). The body is 0-10 mm. 
long by 0-065 mm. in diameter, while the tail is 0-3 mm. long. 
The oral sucker constitutes an anterior protrusion of the body, lying almost 
entirely anterior to the body proper. It has a transverse diameter of 30/x 
and opens through an extremely small anterior pore. Behind it is a short pre¬ 
pharynx followed by a small muscular pharynx. Posterior to the pharynx 
lies the long narrow oesophagus which disappears within the group of cephalic 
glands and cannot be traced to its distal termini. The cephalic glands consist 
of huge masses of mucoid cells filling the middle third of the body. The ducts 
parallel the digestive tract and open laterad to the oral suctorial pore. The 
excretory system consists of a singularly small central bladder with dorsal 
pore, and three main canals, two running antero-laterad in the body and one 
through the middle of the tail, terminating in a pore at its distal end. This 
caudal canal seems, therefore, to be a drainage rather than collecting tube. 
The flame-cells and capillaries of the system have not been made out. The 
genital anlagen consist of a group of undeveloped cells lying medially behind 
the cephalic glands. The ventral sucker is vestigial, containing only glandular 
elements. 
C. chromophila develops in a simple sacculate redia, which lacks feet, 
birth-pore or any other differentiating features except a well-developed pharynx 
and small rhabdocoel gut. Small cystogenous granules are found throughout 
the body. While cyst formation has not been observed it seems highly probable 
that this process occurs and that the distomule is transferred passively to the 
next host. 
Cercaria abbrevic iuda nov. spec. 
(Plate XXII, Fig. 19.) 
This microcotylous larva, for which the name Cercaria abbrevicauda is 
suggested, is ovate in outline with a small knob of a tail consisting of un¬ 
differentiated parenchyma. The body measures 0-1 mm. in length by 0-06 mm. 
in width and is covered with minute spines. The larva was found in a 0-6 per 
cent, infection of Melania ebenina Brot. collected at Kiukiang in August, 1921. 
The oral sucker is the largest organ in the body. It measures 40 /x in trans¬ 
verse diameter and is slightly longer than broad. The ventral sucker is less 
than half this diameter. The dorsal lip of the oral sucker is much thicker and 
more pronounced than the lower lip. There is a mucoid stylet inserted in the 
dorsal lip, which can be readily protruded and retracted. Within the oral 
atrium is a small pharynx which has lost its muscular function but serves as 
the focal centre of mucoid pharyngeal glands ( pg ) which envelop the area. The 
remaining parts of the digestive tract, consisting of oesophagus and caeca 
have not been found after careful search. Cephalic glands are of two types. 
There are paired groups of probably ten mucoid basophilic glands strung in 
tandem arrangement from pharynx to excretory bladder. In the pre-acetabular 
region there are also four pairs of granular acidophilic glands. All of these 
