448 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Istiophorus nigricans (. Histiophorus gladius), Sail-fish. 
CESTODES. 
1. Diboihrium manubriforme Linton. See under Tetrapterus imperaior, No. 2. 
Xiphias gladius, Swordfish. 
Fish and squid. 
FOOD. 
NEMATODES. 
1. Ascaris incurva Rudolphi. Stomach. [PI. iv, figs. 29-32.] 
U. S. National Museum collection; Casco Bay, Me., 1873. United States Fish Commission steamer 
Albatross , near station 2091, 1883. Woods Hole, Mass., July 25, 1885. Numerous specimens in each lot. 
In the last lot one of the females measures 93 mm. in length; the genital aperture is 30 mm. from the 
anterior end. Some small specimens, 12 mm. in length, are the young of this species. The following 
note was made at the time of collecting: One of the largest measured 267 mm. in length and 3 mm. 
in diameter. Some of the worms were of a greenish color; smaller ones, with a red-brown stripe; very 
small ones, hair-brown; two or three, quite dark brown. 
CESTODES. 
2. Dibothrium plicatum Rud. Intestine. 2 , pp. 746-750, pi. in, figs. 1-6. 5 , pp. 430-431. 7 , p. 278. 
3. Rhynchobolhrium attenuatum Rudolphi. Peritoneum. 4 , pp. 805-806, pi. lxv, figs. 8-11. 7 , p.278. 
4. Tetrarhynclius bicolor Bartels. Peritoneum and mesentery. 4 , pp. 813-815, pi. lxviii, figs. 1-6. 
TREMATODES. 
5. Tristomum coccineum Cuvier. Gills. O, pp. 509-510, pi. xl, fig. 9. 7 , p. 278. 
6. Distomum clavalum Rudolphi. Stomach. 0, pp. 539-540, pi. liii, figs. 8-11. 
COPEPODS. 
7. PhUichthys xiphise Steenstrup. July 19, 1900. 
Six specimens of this parasite were found by Mr. C. F. Silvester in the frontal sinuses of a sword- 
fish head which he was dissecting. These were females, with egg cases along the sides, held in place 
between the dorsal and ventral rows of lateral outgrowths of the body, and ranging in length from 
14.5 to 27 mm. General color white, becoming a very faint salmon on swollen lobes toward anterior 
end; body along median line slightly darkened by intestine showing through. Egg masses dark 
olive. Dimensions of largest specimen in millimeters: Length, 27; breadth of body at anterior lobes, 
8; at middle, 3; at middle including outgrowths, 10.5. 
Naucrates ductor, Pilot-fish. 
But one specimen examined; no entozoa found. 7 , p. 278. 
Seriola zonata, Pilot-fish. 
FOOD. 
Stomach contents of specimen examined August 16, 1889, half digested fish, probably butter-fish. 
NEMATODES. 
1. Ascaxis incurva Rudolphi. Stomach. 
Two females, collected August 16, 1889. Dimensions of one in millimeters: Length, 22; diameter 
of head 0.19, 1 mm. back of head 0.28, maximum 0.9, 1 mm. from posterior end 0.36, at anal aperture 
0.17; length of head, 0.12; distance from anal aperture to posterior tip, 0.36; distance of reproductive 
aperture from anterior end, 5.5. 
CESTODES. 
2. Tetrarhynclius bisulcatus Linton. Encysted, stomach wall. 4 , pp. 810-811, pi. lxvi, figs. 11-15. 
