50 



THE AMEKICAN MONTHLY 



[March, 



cover with thin glass, and finish as 

 in the case of any fluid mount. 



If the foregoing directions are care- 

 fully followed, and the completed 

 slide be examined -with paraboloid or 

 spot-lens illumination, as well as w^ith 

 ordinary transmitted light, I think the 

 observer -will be well pleased with the 

 result. The process seems to succeed 

 peculiarly -well with the brown hydra 

 (//. Vulgaris) . 



I am inclined to think that with 

 certain modifications the use of this 

 "■hot-water cure" may be given a 

 more extended application, and I 

 should be pleased to learn of any 

 successful attempts in such direction. 



A. H. Breckenfeld. 

 San Francisco, Cal. 



Notes on Steiitor Cceruleus, or the 

 Blue Stentor. 



In studying the infusoria that abovmd 

 in the small lakes in this vicinity, I 

 have occasionally noticed several in- 

 dividuals of the stentor family, and 

 have been somewhat puzzled to ac- 

 count for the presence inside of some 

 of the blue stentors (^S. Cceruleus^ 

 Ehr.) of other infusoria of compara- 

 tively large size, plainly seen through 

 the beautiful transparent ectosarc, 

 which resembles a blue lace bag with 

 a fringe of cilia around the large end. 

 My attention was attracted more par- 

 ticularly to this infusorian by once 

 seeing a stentor with a large Noteus 

 quadricornus inside ; but, not being 

 satisfied whether the noteus was in- 

 side or outside, and knowing how 

 easy it is to be mistaken, I watched 

 the creature long in its graceful wan- 

 derings to and fro in its now limited 

 world under the lens. In course of 

 time the tiny watery world began to 

 evaporate, and the beautiful blue 

 swimmer and his countless compan- 

 ions found themselves becoming 

 nearer neighbors, and the stentor 

 stopped to take in the state of aflairs, 

 and so afforded me a good opportu- 

 nity by focussing to determine that 

 the noteus was indeed inside. Soon 



afterwards the stentor voided an empty 

 carapace, a dead, cleaned-out shell, 

 and went on his way, doubtless re- 

 joicing at his sumptuous repast. My 

 eyes being weary, I took a last look 

 at my blue pet who had given me an 

 evening's instruction and amusement, 

 still puzzled to account for the pres- 

 ence of the noteus in the stentor. 

 The question w^as, How did the no- 

 teus get through that beautifully made 

 oral aperture, fringed with its deli- 

 cate waving cilia, without tearing it 

 all to pieces "^ Last summer, having 

 snatched a few moments from the 

 busy cares of every-day life, I sought 

 out the home of the stentors, and, 

 arriving at their secluded spot, and 

 taking a dip with a small tin spoon, 

 I found on examining the material 

 with a common pocket lens that the 

 water was quite blue with countless 

 myriads of stentors. Filling a small 

 bottle, I hastened home to study them 

 in all their glory, for I have not been 

 able to keep them for any length of 

 time. Upon further examination I 

 found Rotifer viilgaris, Paramecium 

 aurelia^ Coleps hirtus^ and many 

 smaller infusoria in great abundance, 

 upon which the stentors had been 

 feeding quite freely, for the rotifers 

 and paramecia were plainly visible 

 inside — the rotifers in a contracted 

 state and surrounded by a transparent 

 envelope. After watching the oral 

 aperture in vain for some consider- 

 able time, I could not discern that a 

 single rotifer or paramecium passed 

 in that way ; but at last I saw one of 

 the stentors with a rotifer in close 

 proximity, surrounded by the above- 

 mentioned transparent envelope, and 

 after careful observation I have come 

 to the conclusion that the blue stentor 

 not only takes small food particles 

 through the oral aperture, but that 

 it has the means of projecting portions 

 of its protoplasm to serve the purpose 

 of capturing its pre}', for the rotifers 

 and paramecia under consideration 

 were slowly drawn into the body, 

 still surrounded by a transparent en- 

 velope, and were gradually absorbed. 



