142 



THE AMERICAN MONTHLY 



[August, 



Pliialonema Cyclostomum, Stein. 



BY DR. A. C. STOKES. 



Having found this minute creature 

 in some numbers gliding over the de- 

 caying leaves and water-soaked twigs 

 at the bottom of a shallow little pool, 

 the fact seems worthy of record on 

 account of the animalcule's apparent 

 rarity, and because the writer has 

 noted certain points of structure and 

 habit, perhaps of passing importance, 

 yet not set down by former observers. 



Stein's work on the Infusoria con- 

 sists at present of illustrations only, 

 and the scientist who formulated the 

 published generic diagnosis of this an- 

 imalcule did so by describing Stein's 

 figure. It is probably for this reason 



Fig. 25. — Phialonema Cyclostomum, Stein. 



that the American form differs some- 

 what from the detailed account of the 

 genus to which it undoubtedly be- 

 longs. The generic diagnosis states 

 that Phialo7tema is persistent in 

 form, whereas the specimens taken 

 from my little pool are quite elastic. 

 I have witnessed them suddenly and 

 quickly contract into a semi-globose 

 form, with the dilated and obliquely- 

 set oral extremity almost eliminated ; 

 I have seen them variously com- 

 pressed and indented, and with the 

 posterior region twisted or folded. 



The description of the species says 

 that the flagellum of this flask-shaped 

 ci^eature is short, nearly equalling the 

 body in length. In my specimens 

 this organ exceeds the length of the 

 body, and is retractile. The latter 

 accomplishment the creature seldom 

 puts into practice ; it has not been 

 before noted. The pharynx is short, 

 not exceeding one-fourth the length 

 of the infusorian, and apparently does 

 not end in a bulbous enlargement. 

 The body is conspicuously striate, 

 sometimes ridged, obliquely. Its 

 movements are somewhat rapid, the 

 large oral aperture being held in con- 



tact with the slide or supporting ob- 

 ject, the long flagellum distinctly vi- 

 brating only at its distal extremity. 

 The length of the body is -^^-^ inch ; 

 that of the typical species -^\^ inch. 



When the German discoverer's de- 

 scription shall be published it will 

 probably be found to include infuso- 

 ria with flask-shaped, obliquely stri- 

 ate, elastic, and colorless bodies, 

 pointed posteriorly, prolonged ante- 

 riorly in a neck-like manner, the ex- 

 panded oral aperture circular, trun- 

 cate, and obliquely set, the rim thick- 

 ened ; pharynx cui'ved, tubular, at 

 times extending to or beyond the' 

 centre of the body, its distal end oc- 

 casionally much dilated ; cuticular 

 surface spirally striate or ridged ; fla- 

 gellum vibratile, retractile, often 

 longer than the body ; nucleus sub- 

 central ; contractile vesicle anteriorly 

 placed, at one side of the pharynx. 

 Length of body yoVo ^° tto i"ch. 



Taking into consideration the dif- 

 ferences between my find and the type 

 as published, I think it desirable to 

 record the infusorian, if not identical 

 with Philalonema cyclostomum^ at 

 least only as an American variety. 

 It is shown in figure 25. 



A Rapid Method for Making Bone 

 and Teeth Sections. 



BY EVERETT T. NEALEY, M. D. 



An article in the yournal of the 

 Royal Microscopical Society^ 1884, 

 page 304, by Mr. J. E. Ady, forci- 

 bly brings to mind the laborious chai"- 

 acter of the methods in common use 

 by workers upon teeth and bone prep- 

 arations. 



I have spent some time trying to 

 follow out the instructions usually 

 recommended in text-books, gluing 

 thick, sawed sections to slips of 

 glass, and after grinding and polish- 

 ing one side, turning the sections over 

 and following the same course upon 

 the opposite side. As the section 

 necessarily became dry and brittle, I 

 at last gave up the plan as unsatisfac- 

 tory, especially for one having other 



