1900] MICROSCOPICAL JOURNAL. 275 



f'ormis. But Hyalodiscus was not named then and it had 

 to be placed in a genus Cyclotella named from the Greek 

 of a circle and it was so named, and as it was found on alga 

 along the coast of Scotland the name Scotia was used as 

 the specific name. But we notice in the figure in Die 

 Kieselshalligen bacillarian oder diatomaceen, 1844, that 

 Kuting has given it as growing attached by the edge of 

 the valve and singly, not in chains. This is what I found is 

 the way of growing large Trochiscia in the Alaskan speci- 

 mens and other Pacific coast specimens. Thus the Tro- 

 chiscia grows. Let us see how it multiplies. For in 

 multiplication the product is much greater than by grow- 

 ing. The individual grows in size, that is to say an indi- 

 vidual does not increase in size itself but it forms a new 

 individual which is larger than its parent and this is call- 

 ed a gonidium (gonidia in the plural). And this may be 

 exactly like the parent, except in size, or it may be un- 

 like, so unlike that it may look another genus, — e. g., Hy- 

 alodiscus. As Kabenhorst in Tab. x in Die Susswasser 

 diatomaceen, 1853, gives the formation of the gonidium 

 in Melosira varians and even the spores, which he gives 

 as possessing cilliae by means of which it swims about 

 when the shell of the gonidium is ruptured as he says is the 

 case. These spores are numerous and move about and 

 disseminate the form so. This seems to be the way Tro- 

 chiscia forms spores. 



Amoeba Having no Vitality. 



ARTHUR M. EDWARDS, M. D. 

 Amoeba is a mass of matter having and possessing re- 

 markable powers of motion. It moves about by something 

 which is known as vitality, for want of abetter name, and 

 hence the amoeba is reckoned as a living thing, an animal. 

 This was the fact some time ago. But now amoebas are 

 known as vegetables, that is to say the protoplasm of veg- 

 atables is known to take upon itself amoeboid motion. 



