470 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Dimensions in millimeters: 
a. 
b. 
mm. 
1.21 
mm. 
0.88 
.43 
.45 
Length of oral sucker 
.16 
.16 
Breadth of oral sucker 
. 11 
.13 
.20 
Length of acetabulum 
. 17 
Breadth of acetabulum 
.23 
.28 
. 11 
. 17 
.10 
. 11 
.045 
.024 
8. Monostomum vinal-edwardsii sp. nov. [PI. xxxiv, tigs. 373-376.] Aug. 5, 1899; 7. July 26, 1900; 
Aug. 4 and 10, 1900; numerous. Young and adult together in same lot. 
The following preliminary synopsis of these interesting trematodes is here given: Body thickish, 
depressed, slightly convex above, flat below, outline varying but approximating ovate, covered with 
exceedingly minute villous spines. Oral sucker circular, subterminal, aperture nearly circular. 
Pharynx varying in preserved specimens, subglobular in life near oral sucker, but in favorable positions 
seem to be separated by a short canal. (Esophagus short; intestinal rami two, simple, extending to 
posterior end of body. Testes in the larger specimens apparently eight, four on each posterolateral 
margin (in one specimen there were five on the right side and four on the left) . In smaller specimens 
the testes are in two lateral clusters of four or five or more testicules each, situated at about the posterior 
third, which in such specimens is usually the widest part of the body. Seminal vesicle on median line, 
curving to the left, the cirrus opening by an acetabuliform aperture about the anterior third. The 
vitellaria are dendritic organs, distributed general^ in the posterior part of the body behind the 
genital acetabulum in younger specimens, confined to the lateral regions of the middle third of 
the body of older specimens. Ovary a many-lobed organ on the median line a short distance behind 
the genital acetabulum, from which it is separated by the seminal receptacle and base of the cirrus 
pouch. Excretory vessels very numerous in the anterior third of the body, each opening independently 
on the surface. Uterus very voluminous, in the older specimens filling up all the posteromedian part 
of the body. Ova rather small and elliptical. Dimensions of a living specimen slightly compressed, in 
millimeters: Length, 2.36; diameter of oral sucker 0.25, of pharynx 0.15, of genital acetabulum 0.13; 
ova, 0.021 and 0.010 in the two principal diameters. At certain ages there is a very characteristic 
coloration in these worms, due to the different ages of the ova. The beginning folds of the uterus on 
the left side are opaque white; the next, toward the posterior and on the right side, are light yellow, 
shading into amber and smoky brown, becoming much darker toward the anterior. 
The external opening of the uterus was not made out, although a minute aperture was noted in 
one specimen which had lain over night in salt solution 0.07 mm. in front of the genital acetabulum. 
This point will doubtless be settled when the specimens are sectioned. 
Prionotus carolinus, Sea Robin. 
FOOD. 
Stomachs and intestines of this species have yielded a varietjr of material. In one specimen were 
found a young herring, several young clams ( Mya ), two shrimp (PaLrmonet.es), and a pebble. Small 
specimens have yielded shrimps in large numbers, amphipods and other small crustaceans, squid and 
lamellibranch mollusks, annelids, and seaweed. One small specimen had four young winter flounders 
in its stomach 
NEMATODES. 
1. Immature nematodes. On serous covering of viscera. Aug. 21, 1899; Aug. 21, 1900; few. 
Some immature ascarids collected July 21, 1887, encapsuled in peritoneum. Dimensions in 
millimeters: Length, 20; diameter of head 0.11, 1 mm. from anterior 0.27, maximum 0.56, 1 mm. from 
