Dr. G. C. Wallich on the Distinctive Characters in Amoeba. Ill 



species might be given merely by the terms spharenchyma and 

 ovenchyma. 



In both species the sides of the cells are somewhat flattened 

 from mutual pressure ; and the intercellular passages are either 

 very nai'row or not easily seen when the parts are quite moist. 



Fig. 1 . Outlines of leaf-cells of H. Tunbridgense. 

 Fig. 2. The same of H. Wilsoni. 



[Both drawn to the one scale of y^o^tli of an inch.] 

 Edenbridge, July 9, 1863. 



XIII. — On the Value of the Distinctive Characters in Amceba. 

 By G. C. Wallich, M.D., F.L.S., &c. &c. 



In a series of papers published in the 'Annals and Magazine 

 of Natural History' for April, May, and June, 1863, I adverted 

 to the absolute necessity of long-continued and daily observation 

 whensoever it is desired to elucidate the characters and vital phe- 

 nomena which appertain to the lowest and, at the same time, the 

 most minute forms of organic existence — my remarks on this 

 head having been specially prompted by the truly Protean 

 aspects under which Amoeba villosa presented itself to my notice. 



A fourth month's close study of that form has not only lent 

 additional force to my previous descriptions, but, whilst it en- 

 ables me to speak with still greater confidence on the subject, it 

 also demonstrates in a striking degree, as I shall presently show, 

 the fallacy of attempting to arrive at a correct knowledge of the 

 characters and ever-varying phases of such an organism under a 

 less laborious and protracted examination. 



After the last paper of my series was completed, namely, on 

 the 20th of May, Mr. Carter called on me; and for the first 

 time I made the acquaintance of a naturalist whose researches 

 amongst the lower forms of animal life have always been justly 

 regarded as well worthy of attention. On a subsequent occasion. 



