408 UTPvICULAEIA NEGLECTA. Chap. XVII. 



spread analogy, this would have rendered them more 

 sensitive to irritation, or would by itself have excited 

 movement ; but no effect was produced. We may, 

 therefore, conclude that animals enter merely by 

 forcing their way through the slit-like orifice ; their 

 heads serving as a wedge. But I am surprised that 

 such small and Aveak creatures as are often captured 

 (for instance, the nauplius of a crustacean, and a tardi- 

 grade) should be strong enough to act in this manner, 

 seeing that it was difficult to push in one end of a 

 bit of a hair i of an inch in length. Nevertheless, 

 it is certain that weak and small creatures do enter, 

 and Mrs. Treat, of New Jersey, has been more suc- 

 cessful than any other observer, and has often wit- 

 nessed in the case of TJtricularia clandestina the 

 whole process.* She saw a tardigrade slowly walk- 

 ing round a bladder, as if reconnoitring ; at last it 

 crawled into the depression where the valve lies, and 

 then easily entered. She also witnessed the entrap- 

 ment of various minute crustaceans. Cypris "was 

 " quite wary, but nevertheless was often caught. 

 " Coming to the entrance of a bladder, it would some- 

 " times pause a moment, and then dash away ; at 

 " other times it would come close up, and even ven- 

 " ture part of the way into the entrance and back out 

 " as if afraid. Another, more heedless, would open 

 " the door and walk in ; but it was no sooner in than 

 " it manifested alarm, drew in its feet and antennae, 

 and closed its shell." Larvae, apparently of gnats, 

 when "feeding near the entrance, are pretty certain 

 " to run their heads into the net, whence there is no 

 " retreat. A large larva is sometimes three or four 

 " hours in being swallowed, the process bringing to 



New York Tribune,' reprinted in the ' Gard. Chron.' 1875, p. 303. 



