228 Infusorial Circuit of Generations. 



own, which perdure exsiccation. In the class of Fungi we meet 

 with similar examples, as e. g. in the case of the yeast-plant, which 

 can endure a considerable degree of exsiccation without impairing 

 the vitality of those c^-conients, which actually exercise the fer- 

 mentive energies and also consume the old cell-coat {not common 

 cellulose, by the way) in this process of reviving. Likewise, the 

 vermilion, gummose (tubercularia) pimples on rotting Black Oak 

 branches can endure a baking process in the burning sun, but still 

 revive on contact with water. Its spicular " spermatia " {fusidium, 

 resembling Naviculae or magnetic needles) at once assume an oscil- 

 latory motion and swell up to the size of those didymous (trichothe- 

 ciuni) spores which presently stand erect on pedicels, as a pink 

 velvet, in the chinks of the bark and collapse at the first touch of 

 the sun ; while their ultimate subcortical development into a mature, 

 " black enamel " Sphaeria again perdures in the heat. 



Under the circumstances above mentioned, the rain water and 

 dry dust carried by the wind to the roof, and thence collected into 

 a perfectly dry tub, itself standing on a similar roof, within a few 

 days was found swarming with all the minor phases of the Vor- 

 ticello-planarian germ-developments. Both the bodies and the yolks 

 or gemmae of the latter occasionally become reduced, by spontaneous 

 dissolution, into very minute particles, each in the wet state capable 

 of resuming the regeneration of individual germs. Judging from 

 analogy, it is but reasonable to suppose that it is this reduced nube- 

 cular and molecular condition, which adapts them to last and survive 

 in a dry condition, as we find it not only with the Fungi, but also 

 in the case of the pruinose-pulverulent, primitive moss-spawns, all 

 three agreeing in this feature of being "reduced to dust," out of 

 which they are again resuscitated. This evanescent condition, how- 

 ever, where gelatinous particles of about <yoVo of a hue diameter 

 shrink alike to imperceptible dimensions, affords no pretext what- 

 ever for assuming identities, just because we ourselves lose the means 

 of diserimination. Whenever the identity of S'uhstance is preserved, 

 each of these various molecular organisms preserves its cyclar de- 

 velopments distinct from similar, corresponding ones as true species, 

 so far as my observations go. 



There being, at present, no comprehensive pictorial works avail- 

 able to fall back upon for reference, that are sufficiently correct, 

 even in their designs, to identify the forms, allowance must be made 

 for the liberties of comparison taken in the following descriptive 

 representation of the most frequent infusorial processes. 



On extensive clay formations, all over the central part of the 

 Mississippi valley, the first appearance, in the warm season, of 

 vegetable life, e. g. in water-pools recently formed by rain, &c., is 

 mainly that of " Chlamydococcns j>luvialis" even where the clay is 

 immediately taken from the deepest excavations. As the sequel of 



