162 UTRICULAR STRUCTURES. 



accurate methods of investigation showed that what had 

 been considered hollow, was really solid. 



It was further attempted to show, in some granules, 

 that their mode of origin was analogous to that of crystals 

 and different from that of cells. They were supposed 

 to be produced by a nucleus, through the deposition of 

 layers on the outer surface. 



Particular theorists persisted in the view that the for- 

 mations in the contents were utricles, the analogy to a 

 cell floating in their minds. The empirical proof that 

 such an agreement existed was not given. 



In the present condition of the researches, therefore, 

 the questions are : whether the so-called granules exhibit 

 analogy with the crystal or the cell ; whether they are solid 

 or hollow ; whether they are formed by the deposition of 

 layers around a nucleus or in some other way ? 



The first question is to be solved by the decision of 

 the last two. The second is, of course, to be answered 

 with the statement., that as a rule the so-called granules 

 appear solid. But this does not establish anything in re- 

 gard to their nature, since utricles may become or appear 

 solid in various ways, while granules may at the same 

 time be hollow. The answer to the third question alone 

 possesses scientific interest, since it decides incontestably 

 as to the crystal-like or cell-like nature. 



Thus the entire question turns upon this : Do the 

 structures in the cell-contents originate by stratified depo- 

 sition from without, and do they fulfil a vital process cor- 

 responding to this crystal-like mode of formation ? or, on 

 the other side : Do they originate in a similar manner 

 to the cell ; do they consist, like this, of a membrane and 

 contents inclosed by this membrane ; and do they exhibit, 

 in general^ in reference to the contents and membrane, ana- 

 logous alterations during their life, to those we are 

 acquainted with in the cells ? 



Some time ago I pointed out two utricular structures 

 in the contents of cells, the nuclear utricle,* and peculiar 



* SchleidenundNageli, Zeits. f. wiss. Bot,, i, p. 68; Ray Trans., 1845, p. 246. 



