256 Mi\ H. J. Carter on FtUgerous Oreen 



rina and the Volvoces the divisions are fixed to the inner sur- 

 face of the parent cell, with their two cilia projecting exter- 

 nally, affording still further probability that the 4-ciliated cell 

 is the primary phase of Eudorina. 



Cells of this kind vf'iih. four cilia are very common both in 

 fresh and salt water ; and thus the ciliated character is of less 

 consequence than the form and size of the cell itself, which 

 varies much, and perhaps may be found indicative in many 

 instances of the species of which it may be the sporozoid. 



It may be also a question Avhether the ovoid cell which I 

 have just described may not sometimes assume a different 

 form ; for on one occasion I find figured with it a spherical one, 

 but identical with the ovoid one in size and all other respects. 



Still, be this, too, as it may, we shall never know anything 

 definitively about these forms, or the species to which they 

 respectively belong, until they are all brought together into 

 their respective groups ; for then, and then only, shall we be 

 able to clear up the utter confusion of phasial differences which 

 may exist in even one drop of water, in this department of the 

 filigerous Infusoria. 



Perty places the 4-ciliated cells among his " Sporozoidia " 

 (p. 102), and figures an oval one (tab. 10. fig. 9) with a notch 

 in front, but with no red eye-spot, which he likens to Chlaviy- 

 domonas. He also, as before stated, likens Ehrenberg's Cryges 

 to the latter. Lastly, Cohn (a^^. Pritchard, p. 524, ed. 1861) 

 considers Gyges to be the still fonii of a cell of Protococcus. 

 But, whatever Gyges may be, Ehrenberg's figures of it are 

 natui'ally so meagre that further conjecture respecting them 

 becomes useless. 



Of what value, it may now be asked, is the number of cilia 

 characteristically, when, as we have just seen, the small sub- 

 divisions of a 4-ciliated cell are only provided with two cilia 

 each ? Certainly it does not militate against the view that 

 the 2-ciliated Eudorina-ceW does not originally arise from the 

 small subdivisions of the 4-ciliated one. Moreover the 4- 

 ciliated cell is the sporozoid of several filamentous Algse, 

 which, of course, have no cilia as such, any more than the still 

 forms of the unicellular Algffi. 



To return to our subject of the phasial forms of Eudorina 

 in Ehrenberg's plate 2. figs. 33 & 34, viz. Pandorina morum 

 and P. hyalina, both appear to me to be large parasiticized cells 

 of Eudorina. The first represents tlie cells of Eudm-ina under 

 difterent degrees of subdivision, and the latter where they 

 have passed into the spermatoid condition. Here, again, there 

 is only one cilium. I think there should be two. 



Lastly, Perty's Synaphia Dujardinii (fig. 8 G, tab. 11) ap- 



