133] PROTEOCEPHALIDAE—LA RUE 133 



head and neck changed their position and shape so rapidly that it was with the 

 greatest difficulty that trustworthy measurements could be made: 



Millimeters. 



"Breadth of head 0.28 



Diameter of acetabula 0.12 



Diameter of neck, narrowest part 0.20 



Distance of first segments from head 17.00 



Length of fourth segment from end of strobile 1.30 



Breadth of same, posterior end 1.50 



Breadth of same, anterior end 1.60 



Length of posterior segment 0.90 



Breadth of same, posterior end 0.60 



Breadth of same, anterior end 1.25 



"Habitat. — Common Eel (Anguilla vulgaris) ; intestine ; Wood's Hole, Mass., 

 August 26, 1885; one specimen." 



"Von Linstow (Compend. der Helminth., 1878) records but two Taenia from 

 the Common Eel, T. macrocephala Creplin and T. hemispherica Molin. T. dilatata 

 is very different from the former. Diesing (Revis. der Ceph., Ab. Cycl., p. 378) 

 mentions the latter, but gives no enumeration of characters. I do not have access 

 to Molin's paper, and cannot, therefore say whether T. dilatata is identical with 

 his species or not. The peculiar inflated character of the neck suggests T. ambigua 

 Dujardin, but the difference in size between the adult specimens is alone sufficient 

 to render the union in the same species impossible." 



Again Linton (1897:425) reported this species from A. chrysypa 

 thus: 



"Taenia dilatata Linton. — No. 4812 U. S. N. M. From common eel (An- 

 guilla chrysypa). Several strobiles but in bad state of preservation, no scolices; 

 anterior ends have been exceedingly long and slender. The characteristic dilata- 

 tions of this species can not be proved from these specimens. The general ap- 

 pearance of the strobiles, as well as the character of the segments, however, agrees 

 with this species. 



"It may be added that the segments of these specimens agree with Molin's 

 description of his T. hemispherica. With the evidence at hand, however, the 

 writer does not feel justified in uniting the two species of T. dilatata and T. 

 hemispherica." 



Professor H. B. Ward secured this material, No. 4812, U. S. N. M. 

 for my examination but its state of preservation was too poor to permit 

 any positive determination being made, 



Linton (1901:435) recording the parasites of Anguilla chrysypa 

 reported this species again. '^Taenia dilatata Linton. Specimens of 

 this genus also taken in 1899, three on August 2. Dimensions in milli- 



