112 Dr. G. C. Wallich on the Value of 



I endeavoured to exhibit to him^ as far as his time permitted, 

 the characters of Amoeba villosa as then observable in living 

 specimens taken from my aquai'ium, dwelling strongly, how- 

 ever, on the marked changes which had already taken place in 

 them under the unfavourable conditions of long captivity. 



Courting, as I have avowedly done, the fullest scrutiny into 

 the characters and vital phenomena of the Rhizopods alluded to 

 in my descriptions, I confess I was by no means prepared to 

 find that, under an evident misapprehension of my meaning, 

 the view entertained by me throughout my protracted survey 

 of the Amoeba villosa (namely, that probably many, if not all, 

 of the previously described forms of Amoeba are referable to, 

 and constitute mere phases of, this the most highly developed 

 type*) should have been adduced in support of the statement 

 that Amoeba villosa is now regarded by me as identical with A. 

 princeps only. 



That such has never been my belief may be gathered both 

 from my own account of the first-named species, and from a 

 note appended to the resume of my papers by Mr. H. J. Slack, 

 which appeared in the July Number of the ^Intellectual Observer,' 

 simultaneously with Mr. Carter's notice on A. princeps in the 

 * Annals.' 



Much as I regret the necessity of having to become the critic 

 of Mr. Carter's opinions, in order that I may adequately sustain 

 my own, I must state my reasons for declining to subscribe to 

 many of the conclusions at which he has arrived. These reasons 

 will appear whilst I endeavour to establish the four following 

 propositions : — 



1. That it is entirely opposed to usage and rule to change the 

 name under which an object shall have been, for the first time, 

 accurately described. 



2. That the characters of Amoeba villosa, as first brought to 

 notice by me in the three published papers to which allusion has 

 been made, are sufficiently important and distinct from those of 

 any previously described form to warrant their being regarded 

 as typical. 



3. That certain characters regarded by Mr. Carter as of pri- 

 mary importance, and typical of A. princeps (Ehr.) as now re- 

 constituted by him, are distinctive of A. villosa as already de- 

 scribed by me. 



4. That the interpretation put by Mr. Carter upon certain 

 other characters which are common to all the Amoeba is nega- 

 tived by the strongest evidence. 



With regard to the first of these propositions, I beg to state 



* See note at commencement of my first paper in the 'Annals,' No. 64, 

 for April 1863, p. 28?. 



