Notes on Acinetina. By John Badcock. 563 



This being so, Nos. 1, la, 2, and 3, are the immature stages in 

 the life-history of the perfect form now recognized as Podoplirya 

 quadripartita ; and consequently the new genus Tricliophrya of 

 Claparede and Lachmann must be abandoned. 



One of the forms here figured illustrates the so-called Acineta 

 of Epistylis. Fig. 7 is the Ejnstylis with the Acineta here 

 and there upon its branches, and on first observing it under the 

 Microscope with Mr. Cocks we were inclined to think it a con- 

 firmation of Stein's theory, when my son, whom we had asked to 

 sketch it, remarked that it was not a portion of the Epistylis, but 

 only attached to it. It was somewhat difficult to see the attachment, 

 however, but we were confirmed as to its nature by subsequently 

 seeing it on Carchesium and Ophrydiu7n, as well as by its abnormal 

 position on the sides of the branches of Ejnstylis. 



Since writing the foregoing I have been able to make some 

 further observations of an interesting nature, which I will briefly 

 state. 



I have traced the life-history of one form with tolerable clear- 

 ness. I had often noticed several small round ciliated bodies 

 moving about the field of view, sometimes rapidly spinning round, 

 and then springing with a jerking bound from place to place. On 

 pursuing one of these bodies it was found finally to settle down 

 on a filament of the alga, and gradually to develop a peduncle; 

 then the ciliate character simultaneously changed to that of the 

 Acineta, and finally it gradually branched out to the three- or 

 four-cornered perfect form of Podojjhrya qiiadripartita* 



These ciliated forms correspond to the description usually 

 given to Megatricha imrtita, and in their further development — 

 attached and with a pedicle — to Podophrya fixa. Further I have 

 obseiTed that in the Megafrieha-stsLte they multiply by self- 

 division. May we hazard the inference, in view of these observa- 

 tions, that as not only these, but many other similar forms of life, 

 pass through several life-cycles, in each of which they " increase 

 and multiply," this peculiarity has been the fruitful cause of num- 

 berless new genera and species having been too hastily adopted ? 



* This I have seen in many instances since, and found tlicni to develop on 

 the glass as well as on the weed. 



L' P li 



