AECHEK — ON STEPHANOSPHJEKA PLTJVIALIS (COHN). 163 



And yet, so far as I know, there are but few of the organisms exhibit- 

 ing any of these puzzling or apparently contradictory phases just alluded 

 to, which the most experienced observers have lately, merely on that 

 account, thought fit to remove in their conceptions from the one king- 

 dom to the other. I pass by the futile and uncalled-for efforts of some 

 to form an intermediate kingdom between the animal and the vegetable 

 kingdom. And surely, then, it appears to me, if certain organisms in 

 the one kingdom in the course of their life-history temporarily undergo 

 or simulate those phases which I have alluded to, more especially cha- 

 racteristic of some organisms belonging to the other kingdom, it is, per- 

 haps, at least not more surprising, after all, that a strictly vegetable cell 

 should assume temporarily an amoeboid condition. And it appears to 

 mc that not one of these contradictory temporary phases seems in the 

 least to prove the actual and essential convertibility of an organism be- 

 longing to one kingdom into the other. It is quite true, indeed, that 

 any one looking at one of my amoeboid bodies for the first time, and 

 knowing nothing of its origin, could hardly but believe that it was a 

 true Amoeba, but so peculiar and distinct, even at first sight, as that it 

 could not be mistaken (so far as I can see) for any described Amoeba, but 

 would naturally have been looked upon as a new species. But all mis- 

 conception as to these points becomes altogether done away with, and 

 any such assumptions become wholly set aside, when we know that it 

 was no Amoeba at all, but only an amoeboid state of the vegetable Ste- 

 phanosphsera ; and had it been so described by any one as a new Amoeba 

 in ignorance of its nature, it is probable that some time or other, as the 

 result of subsequent observation, it would, as a species, have shared 

 the fate of many of Ehrenberg's quondam Infusoria, now known to be 

 zoospores of algse, &c. 



But, what the special import of this curious and remarkable excep- 

 tional temporary condition in Stephanosphoera, which I have sought to 

 describe, might be, I cannot dare to take upon myself to conjecture. 

 However, if we seek for and find precedents or examples in the vegeta- 

 ble cell, though some of them may be evinced even in a much less 

 marked degree, of that peculiar contractility exhibited by this organism, 

 while it would not detract from nor diminish the marvel, it would at 

 least lessen the surprise natural on at first witnessing or considering the 

 phenomenon. 



Let us look back, then, in the first place, for a moment, to one or two 

 conditions of Stephanosphaera itself, and I think we shall find that a 

 similar phenomenon presents itself to that forming the subject of this 

 paper, but in a far less marked, therefore at first sight in a far less no- 

 table and surprising degree. 



Let us refer to the typal full-grown Stephanosphsera ;* and, as has 

 been stated, we frequently find the protoplasm of the primordial cells 

 drawn out at each extremity into several filiform, somewhat branched, 



* Cohn., 1. c, Plate VI. , 2, 4, 5, 6, 7. 



