[45] ENTOZOA OF MARINE FISHES OF NEW ENGLAND. 497 



The presence of these parasites in considerable numbers must be in- 

 jurious to the host, since they are always firmly attached and usually 

 cause much local inflammation. In many cases the proboscis was found 

 to have penetrated the walls of the intestine and to be protruding into 

 the body cavity. In most instances of this kind it was surrounded by 

 an abnormal secretion from the tissues of its host. This secretion is of 

 a dark-brown, cinnamon- brown, or amber color. In many cases the pro- 

 boscides were found to have become nuclei, around which were formed, 

 in concentric layers, calculi of this abnormal deposition. The whole is 

 further inclosed in a thickened cyst composed of two or three layers of 

 connective tissue over which is thrown a thin outer covering of perito- 

 neum. A cluster of these encysted calculi, lying in the peritoneum of 

 the large intestine of a specimen of Striped Bass {Roccus lincatus), is 

 shown in Fig. 5; one of the cysts opened, in Fig. 5a-, and a cross-sec- 

 tion of a calculus removed from its cyst in Fig. 5/>. The diameter of 

 one of the largest cysts was 18 mm . In the calculus figured the diameter 

 is 15""". The color on the surface is, when the calculus is placed in al- 

 cohol, a beautiful rich golden-brown with a silky luster. The surface 

 is uneven, with little irregular rounded or mammillary eminences. The 

 nucleus is irregularly linear, Ik to 2 mm in length. The inner layers are 

 thin, irregularly concentric and darker in color than the outer layers. 

 Outside of this central, dark portion is a lighter ring about 2|" !IU thick 

 and made up of a great many thin, concentric layers. This lighter por- 

 tiou is sharply marked off from the remaining outer part of the calculus, 

 separates from it easily, and can be removed from the half-calculus, as 

 one cupel can be taken out of a nest made up of graded sizes. The 

 outer ring is about 3 mm thick, is a little darker than the middle ring, 

 but, like it, is made up of a number of thin, concentric layers. The layers 

 of the two outer rings are more regularly concentric than those of the 

 inner portion. The color of the cut part of the calculus is a little darker 

 than that of the surface, and the luster is waxy. A piece of one of 

 these secretions burned readily and left a small quantity of ash which 

 was composed largely of calcium carbonate. In one, from which the 

 alcohol had evaporated, crystals were noticed which had the general 

 habit and appearance of those of oxalate of urea. 



Alcoholic specimens are uniformly white in color. 



Habitat. — Striped Bass (Roccus Uneatus) ; large intestine ; Wood's 

 Holl, Mass., August and September, ISSI-'So, 

 S. Mis. 90 32 



