Amoebaea'] infusorial ANiMALCutEs. 199 



the microscope) small rounded masses, semi-transparent or nebular, 

 and motionless, but presently an expansion or rounded lobe, quite 

 transparent, may be seen to proceed fi'om the circiimferencc of one or 

 other of these masses ; this expansion insensibly glides along the 

 surface of the glass slide like a drop of oil, and then fixing itself at 

 some point, slowly draws onward the remaining bulk. 



In this mode the vitaHtj^ of the Amceha is manifested, the expan- 

 sions constantly varying in form, arrangement, and number, even in 

 the self-same being. Some constancy in the foi-m and proportionate 

 size of the processes is however, met with in the diflerent Amosbee, 

 and is employed in the discrimination of species. 



Young Amcelce are perfectly transparent, but in proportion as they 

 increase in size, they lose their transparency by the accretion or 

 imbibition of numerous corpuscles or granules, which have been 

 looked upon as ova or the materials of nutrition. Amongst such 

 particles, various matters, derived from without, are found thus 

 imbibed or swallowed, such as starch granules, Naviculae, vegetable 

 debris, &c. Their mode of introduction is accounted for by the way 

 in which the Amcehce move along, their bodies being closely adherent 

 to the surface to which they are afiixed, and also so pressed as to 

 take up any particles in contact, which by successive expansions 

 and contractions become at length imbedded. Before admitting this 

 interpretation of the phenomenon, Dujardin's assumption of the 

 absence of an integument must be admitted. 



But, further, the gelatine-form bodies of the Amcelxs are capable of 

 having vacuolae spontaneously formed, either at, or near the surface, 

 which may ultimately collapse and disappear. By such means, 

 foreign bodies may likewise become introduced within the organism. 

 " It is, however, difficult of belief, that these included particles, 

 by reason of the consistence and imalterability of many of them, 

 can serve to nouiish the Amceha;, but still, whilst admitting that the 

 AmoehiB are noui'ished by absorption, I do not deny that they may 

 find means of still more readily absorbing elements of nutrition, by 

 swallowing various foreign bodies, and of thus increasing their ab- 

 sorbent surface. If it must in aU cases be supposed that these 

 foreign particles enter by a mouth, and are lodged in stomachs. It 

 must also be allowed, that this mouth is produced at any spot, and 



