50 Art. 2.— T. KaV.urakL : 



occurring only in an unused well <>! stagnant water in the Icbigava 

 Ward of Tokyo. 



Of interest is the fact that the Poli/celis-species exhibit a 

 tendency to live on the body-surface of other large animals. As 

 regards this mode of life, we have met such on few occasions in 

 Poll/, auriculaia and Poly, haraflo. In one case the former species 

 is found attached in most abundance to the body of Eichardsonius 

 phalacrocorax (Jordan and Fowler), whereas the latter w^as found 

 living on the carapace of a certain ci"ab as well as on the body- 

 surface of a certain fish and evidentl}^ feeding well on the liver of 

 the crab. 



Food. — The food of several of the species consists, so far as my 

 observations go, largely of small animals. In their digestive tracts 

 have been found certain Crustacea and others. Probably Protozoa 

 makes ideal food because their protoplasm is generally not so 

 thoroughly covered as to bo inaccessible and because they are very 

 common everywhere. Further, the worms make, as already 

 stated, the most vigorous efï'orts to obtain the tiesh of higher animal 

 forms, such as fish. Besides animal food, they also normally, 

 probably to some extent, feed on vegetable matter, which seems, 

 however, to be second in choice, probably because the thick cellu- 

 lose of its epidermis is too armour-like and is beyond the possibility 

 of even receiving an impression from the delicate and jawless lips 

 of the gentle feeders. These substances frequently impart various 

 sorts of hue to the animal, as is observed in PI. gonocephala and 

 some others. During collection, I have used chiefly crushed pieces 

 of a boiled hen's egg. Further, it is an interesting fact that when 

 hungry, a partially crushed specimen of Planaria, even though 

 still able to move about, Avill be seized upon and eaten as quickly 

 as any other food. I have met with such on several occasions. It 

 is, in fact, possible, with a little patience, to make a specimen eat 

 a small piece cut ofï the posterior end of its own bod}'. This eating 

 of each other occurs, so far as I have observed, when an individual 

 is bruised so that some of the tissue underlying the epidermis is 

 exposed. Under these conditions juices escape from the body 

 and act as stimuli on the other worms, as has been stated by 



