FISH PARASITES COLLECTED AT WOODS HOLE. 273 



specimens is interesting when it is remembered that when forms like these are taken from a 

 teague and placed in ordinary sea water or normal salt solution the nematodcs 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-corrosivo lluid bubbles of gas were given oil', indicating the presence 

 of calcareous bodies. 



4. Sphyriia zygaeiia, Hammer-head Shark. 



(1) July 21; one; stomach contained remains of two menhaden. Noeutozoa, in stomach or pylorus. 

 From the spiral valve were obtained two ncmatodes, three scolices of Otobothrium (Entozoa of Marine 

 Fishes, n, pp. 849-853, pi. xin, figs. 9-15; xiv, figs. 1-4), and five specimens of PHoreiobothrium lanium 

 (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 iish. No parasites of any 

 kind found. 



(3) August 18; one; stomach contained fragments of squids; spiral valve yielded a few speci- 

 mens of Phoreiobothrium lasitttn. 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 Plati/bothriuni (Entozoa of Marine Fishes, pp. 

 820-823, pi. vin, 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 cestodo Crossobothrium laciniatum 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- 

 formiug energy is nearly spent I am not certain (Eutozoa of Marine Fishes of New England, part n, 

 pi. vn, fig. 4, p. 800). 



(2) July 23; one; stomach contents not noted, probably empty. 

 Numerous C. laciniatum in spiral valve. 



(3) July 25; one; stomach with partly digested fish, probably flat-fish. 

 Numerous C. laciniatum in spiral valve. 



Numerous Echinorhynchi, partly digested, in stomach ; one in pylorus, evidently introduced with 

 the food. Echinorhynchus acus often occurs in great numbers in the flat-fish (Pseudopleuronectes 

 americanus). 



(4) July 27; three; stomachs contained fish (menhaden). The only parasites found were C. laci- 

 niatum, numerous in each. lu 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. laciniatum in spiral valve. A large proportion of 

 these were youug, 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. laciniatum in considerable numbers in spiral valve. 



(7) July 30; two; stomachs with partly digested fish. Fewer than ordinary parasites in spiral 

 valve. One contained 10 C. laciniatum from 80 to 110 mm. in 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. laciniatum, young and adult. 



(9) AugustS; one; stomach empty. C. laciniatum 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. laciniatum, young and adult, 42 in all, in spiral valve. 



(11) August 18; one; stomach contained the claw of a small crab. C'. laciniatum, 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. laciniatum, but without success. 



F. C. B. 1899 -is 



