1879.] NATURAL SCIENCES OP PHILADELPHIA. 119 



incomplete. The first plate with seven to nine denticles at the 

 outer side of the hook, and with three to four on the inner side 

 (figs, llbb, I2bb). The second and third (fig. 14) with broad basal 

 plate, as (figs, 14, 3) also all the succeeding plates without denti- 

 culation of the inner margin ; on the outer edge (PI. V., fig. 15) 

 a certain number of denticles, increasing to twenty or twenty- 

 five. In the outermost part of the rows the number of denticles 

 decreased (fig. 15) ; the outermost plates were of very variable form 

 (figs. 15a, 4a). The height of the outermost plate sometimes only 

 0.007, generally 0.04-0.05 mm., the height of the next plate about 

 0.06, of the next 0.075 mm.; the height rising to about 0.1 mm.; 

 the height of the innermost lateral plate 0.04, of the fifth 0.06 mm. 

 The color of the plates was pale yellow, the outermost colorless. 



The salivary glands strong, whitish or yellowish, flattened, with 

 a breadth of 1.5 mm., forming two to three short coils at the sides 

 of the oesophagus; the duct very short. The oesophag us, as usual, 

 also the stomach. The intestine emerging from the liver (fig. 

 17a) behind the middle of its upper side; the first part proceeding 

 towards the fore end of the liver, in the largest individuals about 

 5.8 mm. long, somewhat wider in the pyloric part, the descending 

 part of the intestine nearly 13-17 mm. long, with a nearly con- 

 stant breadth of 0.75-1 mm. The liver (in the largest indivi- 

 duals) about 1.3-15.0 mm. long, b} r a breadth of 7-70, and a 

 height of 6-7.5 mm.; about half of the light anterior part strongly 

 flattened for the reception of the anterior genital mass, the pos- 

 terior end rounded ; the color of the surface yellowish-white, the 

 substance (when cut) yellow. The biliary sac whitish, very dis- 

 tinct (fig. 176) on the surface of the liver, about 2 mm. long, 

 laying at the anterior end of the pyloric part of the intestine, on 

 the right side. 



The heart and renal chamber as usual ; the last white, very 

 large, reaching to the fore-end of the liver. The sanguineous 

 gland whitish, very flattened, about 3.5-5.0 mm. in largest dia- 

 meter, covering the central nervous system. The yolk-yellow 

 hermaphroditic gland covering the upper and right side of the 

 liver (fig. 17cc) occasionally with groups of lobes scattered on the 

 under side, but never forming a nearly continuous layer over the 

 liver. The structure was as. usual, with large oogene cells and 

 zoosperms in the lobules. The anterior genital mass large, in 

 the largest specimens 8-8.5 mm. long, 3.5-4.0 mm. broad, and 



