Transmutation of Form in certain Protozoa. 189 



Eotifer is described (p. 603) as having eyes on the proboscis, 

 foot with two terminal toes, and lateral horn-like processes. 



These characters, again, I say are so variable, according to 

 the stage of development, or even temporary elongation, as to be 

 valueless as points of distinction. 



Actinurus (Griffith and Henfrey, p. 14) " agrees with Eotifer in 

 general structure." The point of difference being three and five 

 points to the toes. But this question appears to me so entirely to 

 depend on stage of development and state of projection as to be 

 entirely unrehable as a distinctive mark. 



So far as my few observations have enabled me to form an 

 opinion, I consider that the facts give colour to the opinion that 

 the objects figured in the accompanying Plate (Plate C.) are not 

 only stages of development of one and the same Infusorium, but 

 that these and several other forms are merely developed states of 

 some earlier and more simple forms, which I trust soon to be able 

 to call attention to. 



The subject in aU its bearings is a very large one, and has so 

 close a relation to the Darwinian hypothesis, as well as so important 

 a bearing upon the various schemes of classification, that one is 

 inclined to hope that some sympathy is felt amongst certain classes 

 of microscopists who, like Mr. Chantrell, are able and willing to 

 bear testimony for or against the opinion. Facts " against " are as 

 welcome as facts " for," where truth is the object of search. I trust 

 I shall not be exceeding my privileges in addressing the ' Monthly 

 Microscopical Journal,' if I here take the liberty to say, that if 

 among the readers of the Journal there are those whose pleasure 

 has led them to investigate this question, and whose leisure will 

 permit of their writing upon the subject, if they will, either through 

 the pages of this valuable channel of intercommunication, or by 

 private post, express their opinion either for or against these views, 

 it would confer a favour on all who are solicitous for the publica- 

 tion of truth. It is, I am quite aware, in so difficult a subject as 

 the education of the eye in microscopy, and with the temptations of 

 prejudice to lead one astray, a most easy and probable result of 

 inquiry that it should end in error. But since " ex nihilo nihil fit," 

 and "nothing venture nothing have," are proverbs which have 

 stood the test of experience, I trust I shall be held excusable for 

 having cast loose the anchor of faith in old systems, and venturing 

 my httle boat upon the great sea of speculation and inquiry. 

 There is one writer, whose name is unknown to me, but who is the 

 author of a paper in the ' Quarterly Eeview ' under the title of 

 " Higher and Lower Animals," whose opinion upon classification 

 seems to me so very near the truth, that if this venture should 

 meet his eye it will be esteemed a favour if he would kindly permit 

 me to hear from him, either under a " nom de plume " or otherwise. 



