Mr. H. J. Carter on the Organization of Infusoria. 285 



the disk of Vorticella respectively ? while the granular substance 

 around the other longitudinal and more tortuous canals, which 

 are wholly without tassels, may perforin another excretory func- 

 tion. Lastly, in Nais fusca, where this organ becomes the ovi- 

 sac (see /. c), if I mistake not, the spermatophorous cells are 

 introduced into it through the ciliated opening, — thus still 

 further showing that the currcut of this system is outward. 



The only view, then, that I can take of the vesicula and its 

 vessels is that it is an excretory system corresponding with the 

 renal apparatus in the higher animals ; and if I should be right, 

 then the term '■ vesicula/' which I have adopted for " contract- 

 ing vesicle/' will be still more applicable. It is remarkable, too, 

 that in the Naidina it should be so intimately connected with 

 the generative system, like these two systems in the higher 

 animals. 



Acineta and its Metamorphoses. 



At page 236 of my " Notes/' I have stated, respecting Stein's 

 assumption of the gernmiparous reproduction of Vorticella from 

 Rhizopods, that " Stein has described it in Acineta, and I have 

 since observed it in a Miizopod undistinguishable from Amoeba 

 Gleichenii. I have also seen Vorticella developed singly from 

 Acineta." 



With the latter part of this assertion I have now nothing 

 more to do, since it was an assumption, taking for granted that 

 Stein was right, and I contradicted it as soon as I had an op- 

 portunity of watching the gemmae which are thrown off by Aci- 

 neta sufficiently long to know what became of them. Thus I 

 stated (Ann. Nat. Hist. vol. xx. p. 37, 1857) that, with Lach- 

 mann and Cienkowsky, I never could find that the gemma thrown 

 off from Acineta passes into anything but Acineta. It swims 

 about rapidly by means of its cilia for some time, then becomes 

 stationary, the cilia disappear, and the capitate tentacula are 

 thrown out for catching its prey or food. 



But with the assertion that Vorticella are thrown off from 

 Amoeba, which, on my authority, has been quoted in Dr. Car- 

 penter's work on ' The Microscope' (I think), and in Prit chard's 

 last edition of his ' Infusoria' (p. 36-1), the case is different. 

 This has not been contradicted by me, although I now believe 

 it to be just as much deserving of contradiction as the assertion 

 that the gemma of Acineta becomes a Vorticella. However, as I 

 did witness Amoeba throwing off young living Vorticella, a de- 

 scription of the fact should accompany the view I now take of it. 



Under date the 27th of March 1854, in my private journal, is 

 a full description of this occurrence (with drawings which were 

 then carefully made for publication), which took place in the 

 following way : — 



