444 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
TREMATODES. 
3. Distomum tornatum Rudolphi. [PL xxvm, fig. 310.] Aug. 28, 1899; 30. Aug. 30, 1899; 10. July 
17, 1900; few. See No. 4, under Coryphxna Irippui'iis. 
Maximum size: Length, 11 mm.; diameter, 2 mm. 
The following dimensions in millimeters are from sections, longitudinal vertical: Diameter oral 
sucker 0.22, of pharynx 0.16, of acetabulum (maximum) 0.5, of ovary (maximum) 0.46, of testes 
(maximum) 0.4; ova, 0.017 and 0.012 in the two principal diameters. These worms have a great 
variety of shape and color. In some the intestine is dark-brown and quite conspicuous; uterus, with 
eggs, convoluted in middle portion of body, amber yellow; vas deferens slender, thread-like, convoluted, 
opaque white. As these distomes lay amid the washings from the alimentary canal of the silverside, 
which contained the claws and bits of the shells of shrimps, annelids, and black and white strips of 
the peritoneum of their host, they were rather difficult to distinguish from their surroundings. 
4. Distomum sp. Small, short, fusiform. [PI. xxxii, figs. 357, 358.] Aug. 28, 1899; 6. Aug. 30, 
1899; 2. 
Resembling D. bothryophoron Olsson, but with more slender neck and distinct oesophagus. 
5. Distomum vulde-i.nftaluip JiXossich. In globular cysts, in the liver (July 17, 1900), and in fat masses 
in the body cavity (Aug. 30, 1899). These have spines around the mouth and smaller spines 
on neck. See 6 , pp. 527-528, pi. xlvii, figs. 10, 11, and pi. xlviii, figs. 1,2. 
Mugil cephalus. Jumping Mullet. 
FOOD. 
August 28, 1899; 21, small, 90 mm. to 100 mm. long. July 28, 1900; 12, small. Fish in both 
cases from Waquoit Bay. Alimentary tracts filled with green mud, which contained large numbers of 
diatoms, green algse, an occasional copepod, and much quartz sand, in minute angular grains. No entozoa 
were found. 
Sphyraena borealis, Barracuda. 
FOOD. 
August 8 and 15, 1899; 8, small; remains of young fish in alimentary canal. July 27, 1900; 2, 
small; intestines filled with immense numbers of young univalves, 0.15 mm. to 0.3 mm. in diameter. 
Specimens from Katama. No entozoa found. 
Scomber scombrus, Mackerel. 
FOOD. 
The only food notes I have are for young fish. August 2, 1899; remains of small fish. .August 8 
and 12, 1899; small crustaceans. July 9, 1900; small squid and copepods. 
NEMATODES. 
1. Ascaris. [PI. vm, figs. 73, 74, and pi. xiv, figs. 181, 182.] 
Immature, probably A. clavata Rudolphi; collected by Mr. S. E. Meek, Fulton Market, New 
York, from the stomach of a mackerel, Aug. 30, 1886. Length, 10 mm.; lateral alae very prominent. 
Probably young of A. clavata, but postanal region more elongate than usual in that sjjecies. On 
May 3 and 8, 1899, I received from Dr. H. M. Smith about 80 specimens of nematodes (Ascaris sp.) 
taken from mackerels from the New Jersey coast — the smallest specimen about 10 ram., the others 15 
mm. to 20 mm. in length. One only is adult — a female 40 mm. in length. One male was noted with 
a curved spiculum, which had a strong, opaque costa and a rather broad, transparent blade. Many of 
the smaller specimens are of the type described under the names Agamonema capsularia and Ascaris 
capsularia [figs. 181, 182]; others are undoubtedly ascarids. All are probably immature ascarids. 
Other immature nematodes from the peritoneum have been collected from the mackerel, July 24, 
1889, and Aug. 12, 1899. Specimens collected by Mr. Meek, Aug. and Nov., 1886, were probably all 
young ascarids, although the characteristic jaws of that genus have not yet developed. The longest of 
these measured 28 mm. It agrees closely with Leidy’s description of Agamonema papilligerus Diesing. 
