FISH PARASITES COLLECTED AT WOODS HOLE. 
289 
Distomum appendiculatum Rudolphi ( ?). 
[Plato 3G, figs. 25, 2G, U. S. N. M. No. 6511. [ 
Two small distoma, associated with D. dentation, from tho flounder ( Paraliclithys dentatus), belong 
to the subgeuus Apoblema and appear to bo near D. appendiculatum. The specimens, while quite 
small, are adult, each containing numerous ova. Collected August 27. 
Tho following description is based on a mounted specimen : Body cylindrical, crossed by lino 
transverse strise about 0. C05 millimeter apart. These stri;o are sharp and clear and make a regular 
serrate outline at the margins; neck short, conical, concave beneath; mouth subterminal; acetabulum 
at base of neck about twice tho diameter of the oral sucker, both suckers nearly globular; seminal 
vesicle a short distance back of acetabulum situated toward dorsal side; between it and tho acetab- 
ulum is tho largo prostate and cirrus pouch. Tho external reproductive aperture is on the midventral 
line very close to the mouth; cirrus smooth. The testes are two small subglobular bodies about 0.17 
mm. behind the acetabulum, ventrally placed and lyiug diagonally near together on the median line. 
The vitellaria are two small but well-defined bodies lying ventrally a little toward the right, their 
front margins about half way between the acetabulum and tho end of tho body proper; the right lobe 
is subglobular, the left somewhat thrce-lobed. The folds of the uterus do not extend into the appendix ; 
ova numerous, lying among tho reproductive organs from behind tho testes to the acetabulum; ovary 
globular, lyiug just in front of the vitellaria slightly dorsal to and touching them. 
Dimensions of mounted specimen, in millimeters: Length with appendix 1.13, length without 
appendix 0.92, greatest diameter 0.25, diameter of oral sucker 0.065, diameter of acetabulum 0.12, 
length of pharynx 0.05, diameter of pharynx 0.04, longer diameter of ova 0.027, shorter diameter of 
ova 0.014. 
It will be noticed that while tho proportions of tho suckers are those of I). appendiculatum the 
character of the vitellaria shows a dissimilarity to that species. 
Distomum fcecundum sp. nov. 
[Plato 36, figs. 27-35; Plate 37, figs. 36, 37, U. S. N. M. No. 6512.] 
On September 1 the viscera of live tile-fish ( Lopholatilus chamceleon liceps) taken in 75 fathoms 
of water, south of Newport, R. I., were placed in formalin. On September 5 I examined these viscera 
for entozoa, finding but few, and only one speciman of Distomum. 
The specimen being too thick to permit of a satisfactory examination of the internal structure, 
it was cut into transverso sections. A study of these yielded such interesting results that 1 feel 
justified in recording the following description: Body unarmed, smooth save for transverse wrinkles 
probably due to contraction, thick, bluntly rounded in front, squarish posteriorly; neck slightly 
excavate beneath; mouth subterminal, circular; acetabulum much larger than oral sucker, sessile, 
prominent, its aperture a transverse slit; pharynx subglobular; oesophagus very short; branches of 
intestine simple, extending to posterior end; genital aperture in front of acetabulum a little to right 
of median line; cirrus and pouch for tho greater part dorsal to acetabulum, seminal vesicle dorsal on 
left side just in front of ovary, vas deferens accompanied by prostate from seminal vesicle to cirrus 
also dorsal; ovary dorsal back of posterior third on median line; testes two, transverse, the right a 
little in advance of the other, following tho ovary posteriorly, but situated more ventrally than ovary. 
In sections proceeding from the head tho right testis appears soon after the ovary is first seeu, 
and continues to show in sections after the ovary has disappeared. The shell-gland is ventral to the 
ovary. Vitellaria not abundant in this specimen, which is adult, situated along tho dorso-lateral 
regions of tho body from the testes to the posterior edge of tho acetabulum. The excretory vessel was 
traced from the terminal pore, as a single narrow median canal, to a point in front of the ovary, 
where it divides, the two branches passing one on either side of the acetabulum ventral to the 
intestine. Tho most conspicuous organ in this specimen is the uterus. Its folds fill the body from 
the posterior end to the acetabulum. Both behind and in front of the ovary and testes tho uterus 
occupies the whole cavity, save tho small place occupied by tho intestinal branches and excretory 
vessels. The ova, of which there are immense numbers, are small, oblong-elliptical in outline, with 
thin shell. The contents of a great many of them were stained deeply with carmine. Many of them 
were broken open in the same manner at one end as if a natural line of cleavage existed there, causing 
a terminal cap like part of the shell to separate. The colls which lino the intestinal tract are long 
and project into the lumen with their bluntly rounded and slightly enlarged ends. 
Dimensions in millimeters: (1) Specimen entire in oil of cedar. Length 2.75, breadth through 
F. C. B. 1889—19 
