UTRICUXARIA CLANDESTINA. 145 



its shell ; but after its death the shell unclosed, display- 

 ing its feet and antennae. I never saw even the small- 

 est animalcule escape after it was once fairly inside 

 the utricle. 



So these points were settled to my satisfaction — that 

 the animals were entrapped and killed and slowly mac- 

 erated. But how was I to know that these animals 

 were made subservient to the plant ? If I could only 

 prove that the contents of the utricles were carried di- 

 ■ rectly into the circulation my point was gained. This 

 now was my sole work for several days — to investigate 

 this subject closely. I found the fluid contents to vary 

 considerably from a dark muddy to a very light, trans- 

 parent color. Hundreds of these utricles, one after an- 

 other, were put to the test under the microscope, and 

 I found that to a greater or less extent I could trace 

 the same color that I found in them in the stem on 

 which they grew, though the observation was not so 

 clear and satisfactory as I could wish. After more crit- 

 ical examination I arrived at the conclusion that the 

 cells themselves and not their contents change to a red 

 color ; the stems also take on this color, so as to make 

 it appear as if a red fluid were carried from the utricles 

 into the main stem, which is riot specifically the fact so 

 far as the observations yet made determine ; though the 

 main point, that the contents of the utricles are carried 

 into the circulation, does not seem open to question. 



The next step was to see how many of them con- 

 tained animals, and I found almost every one that was 

 10 



