84 



THE AMERICAN MONTHLY 



[May, 



as a disarranged cluster of extremely 

 fine hair-like rods. Thei'e seems to 

 be no connecting membrane. Dur- 

 ing life the infusorian has the power, 

 which it frequently exercises, of ex- 

 panding the posterior portion of the 

 fascicle and thus apparently separating 

 the constituent rods. After death the 

 latter become entirely free, except at 

 the anterior points of attachment 

 around the oral aperture. The 

 species is the only one thus far re- 

 corded with a single nucleus. 



Perispira strophosoma^ sp. nov. 



(Fig. 13)- 



Body elongate ovate, often some- 

 what curved toward the right-hand 

 side, about four times as long as 

 broad, bearing a ridge-like elevation 

 extending as a single long spiral from 

 the left-hand corner of the oblic^uely 

 truncate anterior border to the evenly 

 rounded posterior extremity ; cilia 

 long and fine, arranged in a row on 

 each side of the spiral elevation ; 

 contractile vesicle single, spherical, 

 postero-terminal ; nucleus ovate, near 

 the centre of one lateral border ; oral 

 and anal apertures not observed ; en- 

 doplasm crowded with small, oblong, 

 dark-bordered corpuscles. Length 

 gi^ inch. Habitat. — Standing water 

 with vSphagnum. Movements rotary 

 on the longitudinal axis. 



The cilia of the general cuticular 

 surface are very fine and extremely 

 difficult to see when the infusorian 

 is swimming ; only when weakened 

 by prolonged confinement beneath 

 the cover-glass, or when dying from 

 the effects of dilute solution of per- 

 chloride of iron, can the observer 

 positively determine their existence. 

 Lacrymaria teres^ sp. nov. (Fig. 

 14). 



Body elongate-clavate, subcylin- 

 drical, very soft and flexible, six to 

 seven times as long as broad, narrow- 

 est and somewhat attenuate and de- 

 pressed anteriorly ; posterior extrem- 

 ity rovmded ; anterior border ob- 

 liquely and convexlv truncate ; cuticu- 

 lar surface finely striate longitudinal- 

 ly ; cilia in the apical groove and on the 



general cuticular surface not con- 

 spicuously differing in size ; contrac- 

 tile vesicle consisting of two con- 

 spicuous spherical vacuoles, one 

 postero-terminal, the other situated 

 in the anterior body-half near one 

 lateral border, the two connected by 

 a narrow, tortuous, canal-like chan- 

 nel penetrating the endoplasm, and 

 often laterally developing spherical 

 or irregular lacunae ; oral aperture 

 terminal ; endoplasm granular. 



Length of body 



TTO 



to .r-i 



1 2T 



inch. 



Habitat. — Standing water w^ith de- 

 caying vegetation from the cypress 

 swamps of South Florida. 



This species differs from L. trim- 

 cat a Stokes, not only in size and 

 more cylindrical contour, but chiefly 

 in the possession of the complex con- 

 tractile vesicles, and in the absence 

 of the remarkably convoluted nucleus 

 characteristic of that infusorian. The 

 animalcules abounded in the habitat 

 mentioned, but in none, even after 

 the repeated application of reagents 

 and staining fluids, could a nucleus 

 be observed. 



The oral aperture is remarkably 

 expansile. Repeatedly the infusorian 

 has been observed to seize Dexiotri- 

 cha plagia Stokes, so that the latter 

 animalcule was at right angles to the 

 body of the Lacrymaria, yet the oral 

 aperture expanded until its width al- 

 most equalled the length of the cap- 

 tured zooid, a length equal to about 



411(1 i"cli- 



Leucophrys ciirvilata^ sp. nov., 



(Fig. 15). 



Body ovate, one and one-half to 

 twice as long as broad, slightly widest 

 posteriorlv, somewhat curved toward 

 the left-hand side, the right-hand bor- 

 der longest, the left-hand margin ante- 

 riorly concave, the dorsal surface con- 

 vex, the ventral flattened ; anterior 

 border obliquely excavate, the poste- 

 rior evenly rounded ; the cuticular 

 surface longitudinally striate ; cilia of 

 the posterior border longest and most 

 conspicuous ; peristome field extend- 

 ing through the anterior one-fourth of 

 the ventral aspect ; oral aperture 



