472 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
about 14 rows of hooks visible counted transversely, and about 16 counted from base to apex. The 
sheath is cylindrical and the lemnisci appear to be a little shorter than the sheath. Dimensions of 
alcoholic specimen, in millimeters: Length, 10; length of proboscis, 0.72; diameter of proboscis, base 
0.34, middle 0.33, apex 0.28; length of longest hooks, 0.06; length of sheath, 1.16; diameter of sheath, 
0.32; diameter of body, anterior 0.58, near posterior 0.43. 
NEMATODES. 
2. Immature nematodes. [PI. xi, figs. 123, 124.] Encapsuled and free. 
Found on each occasion on which this fish was examined. On July 30, 1900, rather numerous. 
The worms were still living when they were examined and appeared to be identical with immature 
nematodes from Urophycis chuss and Paralichthys oblonyus, with which they were compared. Figs. 123 
and 124 are from sketches of a specimen collected by the Fish Commission in 1881. Length, 15 mm. 
CESTODES. 
3. Larval cestodes (Scolex polyrriorphus Dujardin) . Free in intestine. See 'I, p. 789, etc. 
Noticed in material collected August 10, 1899; rather numerous in material collected July 30, 
1900. The latter were still active, the viscera from which they were obtained having been kept on 
ice for two days. They appear to be similar to forms found in the squeteague and other fish, although 
doubtless many species are represented by this well-named Scolex polymorphus. Red pigment patches 
were noted in the necks of these larvre. 
4. Txnia-lilce fragments. Intestine. 7 , p. 282. 
5. Cestode; new. Intestine. [PI. xx, figs. 233, 234, and pi. xxi, figs. 236-238.] 
Two scolices, which appear to belong to an undescribed genus, were obtained from the intestine 
of a tile-fish July 29, 1899. The specimens had been in formalin for two days before I had an 
opportunity of seeing them. The heads and posterior parts were white, the neck and median parts 
pinkish. They were about 6 mm. and 8 mm. long, respectively. The scolex resembles IJcheneibothrium 
in having four unarmed bothria and a terminal muscular disk which is provided with an anterior 
central auxiliary sucker. Each bothrium, considered alone, suggests the genus Phyllobothrium, being 
without transverse costee, having the borders thrown into crumpled folds and being provided with 
an auxiliary acetabulum on its anterior border. The bothria seem to be placed on the head, as in 
Crossobothrium, while they project in the preserved specimens so as to stand nearly perpendicular to 
the flat surface of the neck, as in Calyptrobothrium. The muscular disk in front of the bothria suggests 
the genera Tylocephalum and Discocephalum, while the terminal auxiliary acetabulum, which can be 
seen in the mounted specimen and has its presence fully demonstrated in longitudinal sections, finds 
its counterpart in the genus Echeneibothrium. The auxiliary acetabula on the bothria are concealed 
by the anterior muscular disk and are difficult to see in these specimens. Transverse sections of the 
body show no rudiment of reproductive organs, no differentiation of a central core, only a few 
comparatively coarse longitudinal muscles in the parenchyma. 
The vessels of the water-vascular system are prominent and tortuous, and may be seen along the 
lateral margins of the body, the margins of the bothria, and extending into the muscular disk. Other 
dimensions in millimeters are: Breadth of disk between bothria 1.16, thickness 0.93; thickness of head 
through bothria, 1.31; transverse diameter of head, 1.74; diameter of anterior acetabulum, 0.15; 
breadth of body back of head 1.09, thickness 0.6. 
6. Tetrarhynchus bisulcatus Linton. Scolex. July 30, 1900. 
This specimen agrees with T. bisulcatus, except that the collar is wider than the head, and rugose. 
TREMATODES. 
7. Distomum ocreatum Molin. Intestine. 
Twelve specimens obtained August 10, 1899, agree with the species which I have been recording 
under this name. Length of specimens mounted in balsam vary from 1 mm. to 2.5 mm-. See ii, pp. 
514-515, pi. xlii, fig 13. 7 , p. 288, pi. xxxv, figs. 16-24. 
8. Distomum fcecundum Linton. Intestine. 7 , pp. 282, 289-290, pi. xxxvi, figs. 27-35, and pi. xxxvii, 
figs. 36, 37. 
July 30, 1900; 1, which is probably to be referred to this species. The material from the intestine 
was washed out in fresh water. Some distomes swell up when placed in fresh water, the acetabulum 
