96 MICROSCOPICAL MEMORANDA. 



kingdom, being true Infusoria; that P. viridis is identical with Ehren- 

 berg's Euglenia viridis, and P. nival is with his Euglenia sanguined, (the 

 Enchelides sanguinea and Pulvisculus of authors) ; that these Enchelides 

 " exhibit at times a perfectly motionless state, in which they appear 

 spherical ;" and that in this state they have been described as Proto- 

 cocci ; that, "it is these spherical, reposing animalcules, which often 

 appear in incredible numbers, and, surrounded with a kind of slime, 

 form more or less thick skins, which frequently cover the bottoms of 

 shallow standing waters ;" and it is in consequence of observing that 

 these animalcules, after long remaining in this passive and inert state, 

 occasionally resume their activity, that so many philosophers have 

 spoken of a metamorphosis of Infusoria into plants, and vice versd. 

 Newman's Phytologist, July, 1841. 



Oberhausers New Microscope. Through the kindness of Dr. Andrew 

 Ure, we were favoured with a sight of the newly constructed Microscope, 

 invented by M. Oberhauser, optician of Paris, during his recent visit to 

 London. We do not pretend to give any description of the peculiarities 

 of its construction. It enables, however, the observer to see an object 

 the size of a half-crown piece at one time, and possesses the advantage of 

 not reversing it. The facilities which it affords to the dissector from the 

 above improvement are equally important. On inquiry, we were in- 

 formed, that the price is as near as possible 10, and facilities will shortly 

 be afforded of purchasing them in this country. It is much to be de- 

 sired that some optician, resident in the metropolis, would import the 

 various simple improvements in Microscopes which are continually being 

 made in Germany and France, as many of them are exceedingly good, 

 and of a price more within the latitude of the humbler scientific inquirer. 

 Whoever should undertake this, we promise him every support. Editor. 



Mode of obtaining the Wheel Animalcule, (Vorticella rotatoria.} In all 

 the old books, and in many modern works, directions are given to seek 

 for this interesting animalcule in leaden gutters, when wanted for the 

 microscope ; but I never could find them in such situations, and have 

 not been without them, in one half-pint mug, for the last seven years. 

 My method of raising and preserving this species is the following : 

 Early in the spring I fill a three gallon jug with pure rain-water, (not 

 butt- water, because it contains the larvae of the gnat tribe.) This quan- 

 tity more than suffices to fill a half- pint mug, and to keep it at the same 

 level during the season. I then tie up a small portion of hay, about the 

 size of the smallest joint of the little finger, trimming it so that it may 

 not occupy too much room in the mug, and place it in the water ; or 

 about the same quantity of green sage leaves, also tied and trimmed. 

 About every ten days I remove the decayed portion (with a piece of 

 wire) and substitute a fresh supply. A much greater number of wheel 

 animalcules are raised by the sage leaves ; but I have sometimes been 

 obliged to discontinue the use of it, on account of its producing mouldi- 

 ness. I take them out with an ear-picker, scraping up the sides of the 

 mug near the surface, (including the dirt which adheres to them, by the 

 tail), or under the hay and sage. /. Ford. Chelsea College, June 25, 

 1841. 



