I 



THE AMEKICAN MONTHLY 



[January, 



and to serve for comparison with 

 other samples undergoing examina- 

 tion after maceration. 



Infusoria upon Leaves. 



In reference to the brief notice 

 of Saville Kent's work on the Infus- 

 oria, which appeared in the last issue 

 of this Journal, Mr. J. Sullivant 

 writes as follows : " I would like to 

 hear more of the germs of Infusoria 

 on blades of corn to which you al- 

 lude. Does it not account, in some 

 measure, for the readiness with whit li 

 certain Infusoria make their appear- 

 ance in hay-tea and other vegetable 

 infusions ? " Mr. Kent replies to this 

 question in a very interesting manner. 

 Besides the organisms which are 

 commonly said to develope in hay- 

 infusions, which belong to the genera 

 Paramecium, Colpoda, Cyclidium, Oxy- 

 tricha and Vorticella, he finds a host 

 of others, when the infusions arc 

 watched from day to day, among 

 which are Heteromita {Monas) lens, 

 H. caudata, H. gracilis, Okomonas, 

 Dinomonas, Rhabdomonas, Monas pro- 

 per, Crj^/^z'Zi'^a^, and other flagellates, 

 while Bacteria are always present. Mr. 

 Kent has "positively ascertained," 

 that at least some of these minute be- 

 ings, " are derived from spores which 

 literally encrust with their countless 

 numbers the stalks and blades of the 

 vegetable matter ; these again being 

 the product of preexisting monad 

 forms, whose active life was passed in 

 close association with the green and 

 growing hay under the circumstances 

 hereafter narrated." The experiments 

 which were carried out to elucidate 

 this subject are briefly described. 

 We can only indicate the method of 

 investigation, in the hope that it will 

 lead others to contribute further in- 

 formation on the subject. Hay from 

 different localities was macerated in 

 water which had been previously boil- 

 ed for some time. From the first 

 wetting and simultaneous examina- 

 tion of any given sample, countless 

 numbers of spores were found, most 



of them excessively minute, averag- 

 ing about ^-jr,^inr of ^^ i^^ch in dia- 

 meter. 



In the course of six hours the hith- 

 erto motionless spores were observed 

 detached, they exhibited a vibratory 

 movement, and seemed to resemble in 

 all ways, the members of the uniflagel- 

 late genus Monas. A large proportion 

 of these spores were at first united in 

 clusters, so as to form floating, neck- 

 lace-like aggregations. After a while 

 they separate and each maintains an 

 independent existence. They then in- 

 crease in size, and in twenty-four 

 hours measure ^tjVjt to -^-^-^ of an 

 inch and possess two flagella. They 

 then possess the characteristics of 

 Heteromita. 



It appears that the entire life-cycle 

 of the Infusoria thus found is passed 

 in connection with the plants, and 

 that the spores do not come from 

 the air. They are most abundant 

 upon the lower blades which indicate 

 by their brown or yellow color the 

 progress of decay, where they find a 

 plentiful banquet set for them. Their 

 purpose in life " is to break down and 

 convert into new protoplasmic mat- 

 ter this otherwise waste product;" but 

 to prevent the too rapid increase of 

 these herbivorous species, there are 

 other types, which answer to the car- 

 nivora among them, such as Dinom- 

 Ofias and various ciliata. 



Mounting With Glycerin-jeHy. 



Glycerin-jelly has long been known 

 as a mounting medium, but most per- 

 sons have found some difficulty in its 

 use. The precipitation of balsam by 

 all watery objects, especially aquatic 

 insects and fresh-water algae, induced 

 me to devise the following mode of 

 manipulation, by which glycerin- 

 jelly may be used with great rapidity, 

 avoiding the tedious preliminary pre- 

 paration necessary for balsam. The 

 jelly is made by dissolving trans- 

 parent isinglass in sufficient water, so 

 that it makes a stiff jelly when at the 

 ordinary working temperature of the 



