FISH PARASITES COLLECTED AT WOODS HOLE. 
273 
specimens is interesting when it is remembered that when forms like these are taken from a sque- 
teague and placed in ordinary sea water or normal salt solution the nematodes will continue active, 
often for days, while the cestodes usually cease activity after less than a day. When the cestodes 
were placed in Lang’s aceto-picro-corrosive fluid bubbles of gas were given off, indicating the presence 
of calcareous bodies. 
4. Sphyrna zygaena, Hammer-head Shark. 
(1) July 21; one; stomach contained remains of two menhaden. Noentozoa in stomach or pylorus. 
From the spiral valve were obtained two nematodes, three scolices of Otobothrium (Entozoa of Marine 
Fishes, II, pp. 849-853, pi. xm, figs. 9-15; xiv, figs. 1-4), and five specimens of Phoreiobothrium lasium 
(Cestode Parasites of Fishes, p. 447). The entozoa in this shark were in poor condition, as if partly 
macerated. 
(2) Augusts; one; small; stomach with fragment of partly digested fish. No parasites of any 
kind found. 
(3) August 18; one; stomach contained fragments of squids; spiral valve yielded a few speci- 
mens of Phoreiobothrium lasium. These specimens were exceedingly spiny, but the spines were easily 
detached; bothria had fluted posterior borders, and contracted to about one half their length when 
placed in picro-sulphuric acid; length, 12 to 22 mm. 
Also from spiral valve one specimen of the genus Platybothrium (Entozoa of Marine Fishes, pp. 
820-823, pi. viii, figs. 8-10; IX, fig. 1). See page 300 for description. 
5. Carcharias littoralis, Sand Shark. 
(1) July 21; one; stomach empty. Large numbers of the cestode Crossobolhrium lacmiatum in 
spiral valve (Cestode Parasites of Fishes, pp. 445-446), large and small together; also several of the 
short variety noted in former papers, i. e., forms with mature segments beginning near the head. 
Whether these are to be looked on as a distinct variety or as individuals in which the proglottis- 
forming energy is nearly spent I am not certain (Entozoa of Marine Fishes of New England, part ii, 
pi. vn, fig. 4, p. 800). 
(2) July 23; one; stomach contents not noted, probably empty. 
Numerous C. laeiniatum in spiral valve. 
(3) July 25; one; stomach with partly digested fish, probably flat-fish. 
Numerous C. laeiniatum in spiral valve. 
Numerous Echinorhynchi, partly digested, in stomach ; one in pylorus, evidently introduced with 
the food. Echinorhynchus aeus often occurs in great numbers in the flat-fish ( Pseudopleuronectes 
amerbeanus) . 
(4) July 27; three; stomachs contained fish (menhaden). The only parasites found were C. laci- 
niatum, numerous in each. Iu one they were mainly adult, the longest measuring 42 cm. In one of 
the others a large number were young. These, contrary to their usual habit, were rather firmly fixed 
by their sucking-disks to the intestine. One of the short variety found in this lot. 
(5) July 28; one; stomach with a fish (tautog). Forty-four specimens of a parasitic copepod 
( Pandarus ) on fins. As usual, large numbers of C. laeiniatum in spiral valve. A large proportion of 
these were young, and there were no free mature proglottides, which are always very abundant in lots 
containing mature strobiles. The longest measured about 160 mm. in length. 
(6) July 29; one; stomach empty. C. laeiniatum in considerable numbers in spiral valve. 
(7) July 30; two; stomachs with partly digested fish. Fewer than ordinary parasites iu spiral 
valve. One contained 10 C. laeiniatum from 80 to 110 mm. iu length; the other contained the same 
number, all rather small, 5 to 25 mm. in length. 
(8) August 1; one; stomach with good-sized squeteague which had been bitten into two pieces. 
Spiral valve with numerous C. laeiniatum, young and adult. 
(9) August 8; one; stomach empty. C. laeiniatum in spiral valve, numerous, young and adult. 
(10) August 13; one; stomach empty. The shark had been confined in the pool for several days. 
C. laeiniatum', young and adult, 42 in all, in spiral valve. 
(11) August 18; one; stomach contained the claw of a small crab. C. laeiniatum, young and 
mature, 87 in all, in spiral valve. 
Very careful search was made in the spiral valve of a number of the foregoing specimens of sand 
sharks for other forms than the ever-recurring C. laeiniatum, but without success. 
F. G. B. 1899 -18 
