804 LARVAL CESTODE VAEASITES OF FISHES— LjyTON. 



of the living worm are very beautiful objects, being- quite transparent, 

 while the chitinous liooks have a brilliant vitreons luster. When fully 

 extended, the pioboscides throw themselves into graceful spiral curves. 

 When the pressure is released, if the worm is uninjured, they are apt 

 to be withdrawn. 



The tul)ular neck, when Hattened under the compressor, presents the 

 following features: The center surrounding the proboscis sheaths is 

 filled with large irregular granular masses, closely packed together. 

 Outside of this inner core is a layer of longitudinal muscles, and out- 

 side of this again a layer of vascular tissue, in which the reticulated 

 vessels of the water vascular system can be plainly seen. Outside of 

 the vascular area, and forming the outer coat of the neck, is a layer of 

 dense tissue iu which transverse fibers could be distinguished. 



The water vascular system consists of a network of vessels in the 

 borders of the bothria which connects with large sinuous vessels in the 

 center of the head, and, together with these, with the reticulated subcu- 

 ticular vessels of the neck. Back of the contractile bulbs the system is 

 represented mainly by two pairs of vessels which lie in two sinuous 

 curves near each lateral margin of the embryo. One of these vessels 

 was much larger than the other and ended in a bulbous enlargement. 



Behind the contractile bulbs the body has the appearance of an 

 elongated sac, tilled with granular parenchyma, but with the retractile 

 bodies much smaller than those in the blastocyst. The i)osterior end 

 terminates in a papillary button-like process, which is retractile and 

 covered with a dense coat of minute, straight, hair-like bristles. 



I add a few extracts from notes on some of the foregoing lots. The 

 general account already given was based on specimens from the blue- 

 fish. 



No. 3. Dimensions of specimen, alcoholic, from scup: Length, 27 

 nim.; length of head and neck, 13; length of bothria, 2; breadth of 

 bothrium, 1.0; breadth of neck, 1.5; thickness of neck, 1; diameter at 

 contractile bulbs, 2.5; diameter behind contractile bulbs, 1.7; tapering 

 from behind contractile bulbs to posterior tij), which is 0.5 mm. in 

 diameter. The hooks agree exactly with those on larva from the blue- 

 fish. 



No. 10. Cyst from liver of squeteague: Length 30, mm.; diameter of 

 first third of length, 3.5, tapering thence rather abruptly to ])Osterior 

 end, 1.5. Embryo coiled in larger end; length, estimated, 13.5. Hooks 

 agree exactly with type; length of longer ones, 0.53. 



No. 0. Cyst from abdominal cavity of moonfish : Long pyriform, 

 length, 20 mm.; greatest diameter, 4.5; embryo coiled in anterior 

 fourth; lengthof embryo, 12; of head and neck, 4.<»; diameter of neck, 

 1.5; length of bothrium 1.5, and breadth of bothrium 1.25. Bothria 

 elliptical with posterior emargination and median longitudinal eleva- 

 tion; neck cylindrical with a few transverse wrinkles; hooks agree 

 with type — largest 0.(>5 mm. in length. 



