480 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
attenuate anteriorly, the greatest diameter being not far from the posterior end. The postanal portion 
is slender but more acute in the male than in the female. In the male the posterior end is recurved. 
The body is crossed by very fine transverse striae. The lips are without tooth plates. The upper lip 
is somewhat elliptical, its dimensions in the female being, length 0.2 mm., breadth at middle 0.19 mm., 
breadth at base 0.1 mm. Six postanal papillae were made out in the male, two pairs remote from the 
anus and one pair near. Twelve preanal papillae were seen — that is, two groups of three each — on each 
side; the papillae in the anterior group not so close together as those in the posterior group, which lies 
a short distance in front of the anal aperture. 
Dimensions of the two specimens in millimeters, the numbers for the male standing first: Length, 
33 and 56; diameter of head 0.2 and 0.3, 2 mm. back of head 0.5 and 0.7, maximum (near posterior end) 
0. 68. and 1.46, 2 mm. from posterior end 0.68 and 0.9, at anal aperture 0.24 and 0.5; distance from anal 
aperture to posterior end 0.2 and 1.10; length of oesophagus, male 2.44; length of copulatory spines, 2.3. 
Macrourus bairdii, Baird's Grenadier. 
ACANTHOCEPHALA. 
1 . Echinorhynchus acus Rudolph i. 
U. S. National Museum collection; collected by the U. S. Fish Commission, station 894. Largest 
specimen in this lot measures 21 mm. in length; diameter near anterior end 1.1 mm., near middle 0.8 
nun., near posterior end 0.6 mm. In a male of this lot the number and arrangement of testes, cement 
glands, and vas deferens agreed with the specimens from the flat-fish. See 3 , p. 525, etc. 
NEMATODES. 
2. Ascaris sp. Immature. [PL xiv, figs. 173-178.] 
U. S. National Museum collection, four lots, collected by the U. S. Fish Commission steamer 
Albatross , stations 894, 2201, and 2739. These are all immature and range in length from 15 mm. to 33 
mm. In most of the specimens the embryonic cuticle was still attached, but in the process of sloughing 
off. There is considerable variation in the lips and in the appearance of the posterior end with the 
degree of development. On this account it is exceedingly difficult to characterize these immature 
nematodes briefly. Dimensions of one in millimeters are given: Length, 32; diameter of head 0.17, 
near head 0.25, middle 0.6, near posterior end 0.33, at anal aperture 0.25, 5 mm. back of head 0.65, 5 
mm. from posterior end 0.55; length of oesophagus, 3.3; distance from anal aperture to posterior end, 
0.45. In a specimen measuring 33 mm. in length the greatest diameter was about 10 mm. from the 
posterior end. The body is smooth except for exceedingly minute transverse lines; lateral jaws with 
about three teeth; upper lip without papilla?, at least none were made out; length and breadth of lips 
nearly equal. The interlip in most is very short. 
3. Undetermined nematode. Stomach. [PL xix, figs. 224-227.] 
A nematode which resembles some of the free forms like Enoplus was found in the U. S. National 
Museum collection from the stomach of this host, U. S. Fish Commission station 894. This is one of 
the dredging stations established by the steamer Fish Hawk, October 2, 1880; depth, 365 fathoms. 
The specimens are slender-fusiform, with a tendency to assume an arcuate position. Four pairs of 
small, gently curving spines were counted around the mouth of one of the specimens, and a few others 
a short distance back of the head. The anterior end was retracted in one so that the specimen bore 
some resemblance superficially to Echinorhynchus; posterior end acuminate. Body wall rather thick 
and dense, with a few delicate longitudinal fibers and exceedingly minute and crowded transverse fibers. 
The oesophagus is long and slender. About midway of its length a muscular sheath of coarse 
longitudinal fibers begins, which incloses its basal portion, and, continuing, envelops the intestine and 
reproductive organs. A reproductive opening was noticed in one specimen a little in front of the 
middle in the wall of the muscular sheath. The aperture in the outside wall did not quite coincide 
with it, but had probably been displaced by the distortion of the specimen under the cover glass. 
Dimensions in millimeters: Length, 12.5; diameter, anterior 0.12, middle 0.4, at anal aperture 0.13; 
distance of anal aperture from posterior end, 0.22; length of oesophagus, 1.54; distance of reproductive 
aperture from head, 5.5; transverse diameter of reproductive aperture 0.024, axial diameter 0.018. 
The reproductive aperture was surrounded by a sphincter 0.01 mm. thick. 
CESTODES. 
4. Iihynchobothriuin. Cysts. 4 , p. 796, pi. nxiir, figs. 7, 8. 
