b BULLETIN OF THE 



ruptures of the tegument produced by crushing, or when snipped off 

 with a pair of scissors whilst the animal is feeding, they will present 

 the same curious phenomena. In fact, these curious independent move- 

 ments caused me at first to mistake the organs for viviparous young, 

 and it was not until I had frequently observed the animal feeding, and 

 examined its structure beneath the microscope, after having fed them 

 upon colored food, that I was convinced of their true nature." 



It was these automatic movements of the detached pharynges that at 

 fir.st led me also to believe that they were parasites. They appear as 

 long, white worm-like bodies, one end being truncated, the other ragged 

 and uneven, where it was torn from its attachment. They move about 

 quite rapidly by means of the cilia with which they are covered, and 

 waves of contraction continually pass along the length of the tube 

 from the truncated to the ragged end. The mouth end may be greatly 

 expanded so as to form a funnel-like structure, or it may be so- con- 

 tracted as to obliterate the lumen. I did not succeed in satisfying 

 myself of the real nature of these structures until I examined one of the 

 animals while it was feeding. I placed one of the Lumbriculidae in a 

 watch-glass with a Phagocata, which soon attached itself to the annelid 

 by throwing out its many pharynges, some of which were wrapped about 

 the victim, while others were thrust into its body (Plate II. Fig. 13). 

 The soft parts of the prey were rapidly sucked up and swallowed by means 

 of the peristaltic motions of the pharynges, so that in a short time there 

 was left nothing but the empty and shrivelled integument. 



By far the best reagent for killing is hot corrosive sublimate. An ex- 

 cess of the salt is added to the saturated aqueous solution and the whole 

 is heated to the boiling point. A very strong solution can be prepared 

 in this way, as the salt is more soluble in hot water than in cold. Kennel 

 ('88, p. 455) has recommended the use of 50^, nitric acid. I have used 

 with entire success a modification of his method, viz. a cold saturated solu- 

 tion of corrosive sublimate in 50cf o nitric acid. The worm is placed on a 

 plate in as little water as possible, and when properly extended the fluid 

 is quickly poured over it. After a few minutes' immersion the fluid is 

 replaced by a saturated aqueous solution of corrosive sublimate, in which 

 the worms remain for half an hour and are then washed. I know of 

 nothing else that will kill so quickly, and at the same time leave the tis- 

 sues uninjured. For the study of the intestinal tract, unstained speci- 

 mens were cleared in clove oil. The amount of pigment so obscures the 

 organs lying beneath, that the ramifications of the intestine could be 



