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



boundary line exists between the Rhizopods and the true Infu- 

 soria, it consists in there being, amongst the former, no perma- 

 nent orifice either for the inception or extrusion of foreign or 

 effete matter, and the phenomena of amcfibasis are present ', in 

 the latter, whatever parts exist are permanent formations, and 

 there is either a single or dual orifice for the inception and ex- 

 trusion of substances used for food. 



" Of the peculiar and particular function of the sarcode," says 

 Mr. Carter (Annals, July 1863, p. 36), " there can be no doubt, 

 viz. that of digestion." Now, without calling in question the 

 function, I may be permitted to observe that Mr. Carter takes 

 for granted a most important histological as well as physio- 

 logical distinction between the ectosarc and endosarc, which has 

 only been entertained by Cohn with regard to the Infusoria, as 

 far as I am aware, — namely, that the ectosarc (" diaphane ") is 

 formed from the "sarcode" (or endosarc), and that, "since it 

 has a distinct structure as well as ofiice, having been produced, 

 it is not reconvertible into any other organ by any process but 

 that of digestive assimilation" (Annals, July 1863, p. 37). 



So that having, in the first place, assumed a histological dis- 

 tinction between endosarc and ectosarc, the existence of a spe- 

 cial function is likewise assumed in one, and its absence in the 

 other, whilst an analogy is insisted on between a lower and a 

 higher grade of organisms, — solely, as it would appear, on the 

 ground that the microscope has failed, in both cases, to render 

 visible specialities of structure for the existence of which there 

 is not a vestige of evidence ! 



I am also compelled to avow that the theory put forward by 

 Mr. Carter regarding the pellicula " possessing no adhesiveness, 

 as evidenced by nothing adhering to it which is not seized and 

 kept there by the instinct of the animal," is not reconcilable 

 with a fact to which I drew attention in the 'Annals ' for April 

 (p. 288), or with his subsequent admission to the same effect, 

 contained in his paper (July, p. 43), notwithstanding his pre- 

 viously expressed opinion (p. 32), namely, that the villi exercise 

 a distinct prehensile faculty, and one which unquestionably 

 resides in the external layer of which they are composed, and is 

 quite independent of any grasping action, such as we witness 

 in the rays of Actinophrys. 



Before quitting the subject now under discussion, I may 

 mention that a vast fund of light has recently been thrown 

 on "the development of the organic cell" by Professor H. 

 Karsten, in a paper to which I shall have occasion to refer 

 more in detail at some future opportunity. At present I would 

 merely state that we are indebted to him for having been 

 the first to advance a definition of "cell "-structure conformable 



