No. 5 meserve: monogenetic trematodes 39 



mm. in length by 0.112 mm. in width, single polar filament extends 

 posteriorly, 0.20 mm. in length. 



Discussion. The following observations on the histology of the 

 posterior haptor may be of some interest. Unicellular high columnar 

 gland cells are present in the posterior haptor. They have an almost 

 spherical nucleus slightly anterior to the center of the cell with chro- 

 matin granules aggregated around the nuclear wall. The diameter of 

 the nucleus is over one half the width of the cell. A large area of 

 secretory granules lies just anterior to the nucleus toward the border 

 of the cell which is toward the border of the cell on inside of haptor. 

 Other nonsecretory cells of the haptor are tall, columnar, and slightly 

 wider than the gland cells. They have large elliptical nuclei at their 

 bases. The chromatin is scattered in a network throughout the nuc- 

 leus. The nucleolus was not visible. The gland cells have a heavily 

 staining nucleolus toward one end of the nucleus. 



Comparisons. This species is very similar to B. melleni, which 

 has testes which are smaller, lobed, with two to ten dorso-ventral 

 muscles as compared with larger, smooth testes with eleven to 

 seventeen dorso-ventral muscles. A prostate gland is present in both 

 but is more compact and fan-shaped in B. anadenea. B. anadenea 

 differs from B. adenea in not possessing glands of Goto and in having 

 larger hooks. 



The name anadenea is given to this species since glands of Goto 

 are absent. 



Genus: Entobdella Blainville, 1818 



As previously stated the genus name Entobdella is used in this 

 paper for Benedeniinae with false suckers. 



The following species of the genus Entobdella have been previ- 

 ously described: 



E. bumpsii (Linton, 1900) on Lasyatis centrura. 



E. convoluta (Yamaguti, 1937) n. comb, on Epinephelus akaara. 



E. diadema (Monticelli, 1902) on Solea vulgaris. 



E. hippo glos si (Mueller, 1776), the type species on Spheroides 



annulatus, etc, 

 E. producta (von Linstow, 1904) on Solea vulgaris. 

 E. solea (van Ben. and Hesse, 1863) on Solea vulgaris. 

 E. squamula (Heath, 1902) on Paralichthys calif ornicus. 

 E. steingroveri (Cohn, 1916) on unidentified fish. 



