88 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.64. 



PomatoTnus saltatrix. 



1904, July 22 : 1 plerocercus on viscera ; proboscides partly everted, 

 showing the smallish, recurved hooks at the base, followed by longer 

 recurved hooks on one side, and straightish hooks with notch at the 

 extremity, on the other. 



1906, August 27 : 1, cyst, with plerocercus and scolex. 



1912, August 16 : 1 cyst from pyloric caeca. 



Poronotus triacanthus. 



1913, July 3: 1 cyst, 4,5 by 2.5 mm., in flesh, about 50 mm. in front 

 of the caudal fin, of a fish 22.2 centimeters in length. The wall of the 

 cyst was thin, and loosely surrounded an ivory-white plerocercus, 

 which was moderately active when liberated in sea water, and 

 measuring, at rest, 3.5 by 2 mm. The plerocercus was oblong, and 

 did not show the differentiation into globular and elongated portions 

 usual in this species. A typical scolex was obtained. 



Scoiiibcromorus cavalla. 



1920, August 2 : 3 cj^sts with characteristic plerocerci and scoleces. 

 These were found in a dish containing material which had been 

 scraped from the gills of the fish. The cysts were not seen in place. 



Seriola dumerili. 



1905, October 30: 1 plerocercus of usual type in vial, location in 

 host not stated. 



SYNBOTHRIUM MALLEUM, new species. 



Plate 10, figs. 95-9S. 



Tetrarhynchus crinaceus Beneden, 1897b, pp. 811-812, pi. 57, figs. 1-8. 



1900, p. 281. 



1901, pp. 451, 454, 460. 

 Synbothrium species 1905, pp. 350, 369, 377, 385, figs. 116-118. 



Cestodes found on two occasions at Woods Hole agree in essential 

 characters with the species recorded in my report on the parasites 

 of fishes of Beaufort, N. C, as Synbothrium^ species. 



ScolerC. — Elongate, bothria nearly at right angles to axis, giving a 

 hammer-like effect to the scolex ; bulbs slender, one-third the length 

 of the entire scolex or more; sheathes sinuous or spiral, depending 

 on the state of contraction ; proboscides armed with hooks of a great 

 variety of shapes and sizes, many of them large and strongly re- 

 curved; in a mounted scolex they are seen to vary in length from 

 0.012 to 0.126 mm. 



Dimensions of a scolex, in balsam, somewhat contracted: Length, 

 4.48; length of bothrial portion, 0.84, breadth, 1.54; length of neck, 

 3.64, diameter, 0.77; length of contractile bulb, 1.54, diameter, 0.21. 

 Dimensions of another scolex, in balsam, not contracted: Length, 



