American Represeiitatives of Distomum variegatum. 901 



II. Specific. 



After (^onsiderable deliberatioii, I have ventured upon the follow- 

 ing method of designating these species: 



The generic name Haematoloechus (alf.iaToloixög, blood-licking), 

 as already intimated, lias been given by Looss (1899) to the 

 European forms ; the specific terms longiplexus ' and hreviplexus 

 refer to the lateral folds of the Uterus, varioplexus and simiUplexus 

 express a similarity to the European species H. variegatus and similis, 

 while the posterior median folds of the uterus suggest the word 

 medioplexus. 



1. Haematoloechiis longiplexus n. sp. 



(Plate 33, üg. 1.) 



This was the first of the 5 species with which I became 

 acquainted. It is by far the common est form in the lungs of Piana 

 catesUana Shaw (the Bull-frog), and occurs wherever I have had 

 occasion to look for it; viz. in several localities in Ontario, Quebec, 

 New Brunswick, and Nova Scotia. It does not occur in every frog 

 of the above species but one can scarcely ever open two or three 

 without finding it and often to the number of half-a-dozen, in each 

 lung. I have more than once collected nearly a hundred from six 

 or eight castaway bodies of frogs that had been recently used for 

 physiological purposes; this proved a satisfactory way of obtaining 

 them. 



Most of my adult. mounted examples of this form are 7 or 8 mm 

 in length and about 2 mm in breadth, but of course tbey would 

 measure more when alive. A large living specimen, slightly com- 

 pressed, gave the following measurements : length 15 mm, breadth 

 3 mm, mouth sucker -7 mm. When brought out of its natural habitat 

 this worm is rather a sluggish creature, movements being usually 

 restricted to the anterior end, and it soon becomes entirely motionless. 

 From either surface it is somewhat long-oblong with the posterior 



