PARASITES OF FISHES OF BEAUFORT, NORTH CAROLINA. 345 



and absolute alcohol and kept straightened out by manipulation, still coiled into a spiral at the 

 posterior end. 



The spicules were uot seen extruded in any of the specimens from the bonnet-head, but one Erom 



the small dolphin (tig. L'O) had the spicule projecting, when it was seen to be i lined at (he distal 



end In lateral wings so as to resemble the fluke of an anchor. 



The largest specimen measured was 35 nun. in length and 0.17 mm. in greatest diameter. 



Dimensions of a male in acetic acid: Length 35; diameter of head, not including appendage 0.04, 

 at middle of body 0.17, at anal aperture, uot includingalseO.il; of oesophagus, anterior 0.03, middle 

 0.05, at base 0.07; length of oesophagus 4.2, of longer head appendage 0.14; breadth of head appendage 

 0. 1 : distance from anterior end to nerve-ring 0.45; distance of anal aperture from posterior end 0.25. 



Dimensions of ova in this speeies 0.04 and 0.02 mm. in the two principal diameters. 



1901. — July 24, it. July 25 and 26, numerous. July 27, few. Aug. 6, numerous. Aug. 7, 20. 



1902. — July 18, ii. July 25, numerous. 



2. Rhynchobothrium plicaium sp. nov. [Figs. 132-140.] From spiral valve. 



Strobile slender, active, with tendency to coil up when compressed. Bothria about asltroad as long, 

 their bases not approximate; neck more or less elongated, very contractile, cylindrical, usually with a 

 conspicuous collar-like fold at the contractile hull is, always enlarging at the bulbs and usually narrow- 

 ing again behind them. A patch of red pigment is usually present in the neck in front of the bulbs, 



The contractile bulbs are pyriform or oval, and the retractor muscle, in those eases where the pro- 

 boscis was retracted, could be seen lying in folds at the posterior end of the bulb. Sheaths and pro- 

 boscides long. The proboscides are swollen at the base as in Ji. tumidulum and /.'. tenuispine. The 

 hooks, except at the base of the proboscides, perhaps agree rather better with the latter. Beyond the 

 basal portions of the proboscides they are rather tin ire densel) clothed with hooks than in either of 

 the above-named species. Besides, they are stouter than in /.'. tenuispine and a little stouter, longer, 

 and more curved than in R. tumidulum. 



The segments begin close behind the bulbs, where the strobile may be slightly moniliform. At 

 first they are much broader than long, but they soon become longer than broad, increasing in length 

 rapidly until they are four or five times as long as broad; posterior segments much elongated. Testes 

 conspicuous in two longitudinal, median rows in maturing segments; cirrus long, tapering, and smooth. 

 Vitellaria lateral, ovary two-lobed at posterior end of the segment; vagina opening at posterior side of 

 cloaca, which is at about the posterior third of the lateral edge of the segment; ova longer than broad, 

 and bearing bristles on their surface as in R. tumidulum. Mature segments when full of ripe ova are 

 fusiform, swollen, and dark-brown. 



Dimensions, in millimeters, life: Length of bothria 0.32; breadth about the same; length of head 

 and neck 1.43; length of contractile bulbs 0.32; length of posterior segments 3; diameter of neck 0.17; 

 ova 0.05 and 0.02 in the two principal diameters: diameter of swollen base of proboscis 0.03. 



The preserved specimens are about 10 mm. in length. Since the posterior segments separate 

 rather easily, the actual length is doubtless greater than this. 



Following are measurements of preserved material: Length of head and neck, one specimen 0.8, 

 of another 1.28; contractile bulbs in three specimens 0.14 by 0.07. 0.17 by 0.08, 0.18 by 0.06, length 

 and breadth respectively; diameter of proboscis excluding hooks 0.015, including hooks 0.027: tumid 

 base, excluding hooks 0.024; length of longest hooks 0.01. One specimen was seen which had the 

 blastocyst still attached. It agreed with specimens found in the sharp-nosed shark. (See No. 12 

 under Scoliodon. ) 



1901. — July 8,1. July 24, few. July 25 and 2ti, numerous. July 27, few. Aug. 6, few. Aug. 7, hi. 



1902. — July 18, 12. July 25, 10, one scolex adult, the others short and attached to blastocysts. 

 Dimensions of one of the latter: length of head and neck 1; length of blastocyst 3.75; diameter of 

 head 0.3, of neck just behind head 0.1S, of blastocyst 1.2. 



3. Rhynchobothrium hispidum Linton. 



A single specimen from the spiral valve collected July 18, 1902, is referred with some hesitation 

 to this species. The proboscides were not seen everted, and it is impossible to make out the arrange- 

 ment of the hooks on the inverted proboscis. 



Dimensions, in millimeters, of specimen mounted in balsam, compressed, neck contracted: Length 

 of head and neck 0.6; length of bothrium 0.12; breadth of bothrium 0.12: breadth of neck 0.13; length 

 of bulbs 0.3; diameter of bulbs 0.05; length of proboscis, estimated, 0.45; length of hooks 0.000 to 0.012. 



The contractile bulbs are elongated, and there was a patch of red pigment in front of them. 



