344 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [56] 
This round-worm belongs ¢o the genus which is characterized by the 
possession of a mouth with three lips. It is found only in the Sword- 
fish, and may be readily distinguished by its large size. The male is 
about 55 millimeters in length, the females about 122 millimeters. It 
makes its home principally in the intestines and stomach of the fish, 
causing the growth of morbid tubercles. It has been discovered also in 
the gills and the wsophagus. 
TREMATODA. 
2. DISTOMA DENDRITICUM, Rudolphi. 
Distoma dendriticum, RUDOLPHI, Entozoorum Synopsis, 1819, pp. 93, 364.— 
DuJARDIN, Hist. Nat. des Helminthes, 1845, p. 460. 
Distomum dendriticum, DimsinG, Systema Helminthum, i, 1850, p. 336. 
(This species, as far as I am aware, has never been figured). 
This fluke is peculiar to the Sword-fish. It is lanceolato-ovate in 
outline and quite flat. When alive the color of its body is white, with 
ramifications of black, a character by which it may be distinguished from 
other species. It varies in length from 3.37 to 6.75 millimeters, and in 
width from 1 to 2.25 millimeters. It locates itself in the intestines of the 
Sword-fish, where it is frequently found in large numbers. 
3. DISTOMA VENTRICOSA (Pallas) True. 
Fasciola ventricosa, PALLAS, Spicilegia Zoologica, fascic. x, 1774, p. 18. 
Distoma clavatum, RUDOLPHI, Entoz. Hist. ii, 1809, p. 391.—OWEN, Trans. Zool. 
Soc. London, i, pp. 381-384, pl. xli, fig. 17.—DuJarDIN, Hist. Nat. des Hel- 
minthes, 1845, p. 459. 
This species, which is well displayed in the figure, is somewhat cylin- 
drical in form, but has a globular expansion at the posterior extremity. 
It often reaches a length of two inches, and a specimen five inches long 
and nearly half an inch in breadth is said to have been taken from the 
stomach of a fish captured in the Gulf of Venice. Menzies says of it: 
“In moving, it fastens itself alternately by the ventral aperture and its 
mouth, raising its slender neck between them into an arched form, like 
a leech, and in this manner drags its body along with a slow motion. 
It is of a whitish color, somewhat pellucid, discharging at its mouth a 
black-colored fluid, which can easily be perceived through its body.”* 
It lives in the stomach of the Sword-fish and other fishes. 
4, TRISTOMA COCCINEUM, Cuvier. 
Tristoma coccineum, Cuvier, Regne Animal, 1st ed. iv, 1817, p. 62, pl. xv, fig. 
10.—DUJARDIN, Hist. Nat. des Helminthes, 1845, pp. 322, 323.—BLANCHARD, 
Recherches sur l’Organization des Vers, Ann. des Sci. Nat. 3d series, viii, 
1847, pp. 322-325, pl. x, fig. 2, and pl. xiv, figs. 2-2 c. 
Tristomum coccineum, DIESING, Systema Helminthum, i, 1850, p. 429. 
The species composing the genus Tristoma are characterized by the 
possession of three suctorial disks. 
— 
* Trans. Linn. Soc. i, 1790, pp. 187, 188. 
