36 The Microscope. 



obtained from a vessel in which water had been standing for 

 several weeks on some dead leaves, the water coming from the 

 Delaware river, the leaves — ask the winds. The following des- 

 cription probably contains the essential characters : 



Vorticella rhabdophora, sp. nov. Body elongate, changea- 

 ble in shape, somewhat gibbous, usually obliquely attached to 

 the pedicle, about twice as long as broad, ta- 

 pering posteriorly, widest at the anterior border, 

 beneath which it is somewhat constricted ; the 

 cuticular surface finely striate transversely and 

 also entirely clothed by a delicate, apparently 

 mucilaginous, investment, crowded with short, 

 slightly curved, bacteria-like bodies, which, in 

 transverse optic section, have the aspect of min- 

 ute, solid nodules; peristome border everted, 

 slightly revolute ; nucleus long, band - like, 

 curved, one arm usually extending across the 

 frontal region, and occasionally traversing the 

 ciliary disc ; pedicle commonly less than twice 

 T~ the length of the body; endoplasm colorless, 



granular. Length of body do inch. Habitat. An infusion of 

 leaves. 



The Vorticella is shown in Fig. 1, where the bacteria-like 

 bodies are much more magnified than the infusorian, the repre- 

 sentation being therefore somewhat diagrammatic. Fig. 2 is a 

 diagram of one side in optic section. 



A SIMPLE COVER COMPRESSOR. 



DIVIDE a small cork transversely and cut a notch in one end of 

 one of the pieces. Pass an ordinary stationer's rubber elastic 

 ring over the end of the slide ; put the piece of cork under it, 

 the ring resting in the notch, then draw it along until the under 

 side of the ring will rest under the point to which the pressure 

 is to be applied, then lower the cork on the cover. If more 

 pressure is desired a second ring may be placed over the first. 

 Pieces of cork of different lengths give more or less pressure and 

 those ot different diameters apply it over more or less space; the 



slides can be laid away side by side. 



J. J. Davis. 



