Hyatt.] ■ 66 [Aprils, 
in ju'cofilance witli the prliiciplos of bioi)last()logy eciually .additions 
arising froni organic cellular reproduction and consequently prop- 
erly included under the same heading, and in this category j)artlie- 
nogenesis sliould also be included. All of these are essentially dif- 
ferentiated modes of forming colonial associations of zoons wliich 
are either parts of simple or complex cycles. They corresi)OHd to 
Huxley's individual wliich is defined by him as the whole product 
of one egg. Such cycles of independent beings are naturally 
included under the terms of growth since they are in no sense due 
to rejuvenescence produced by conjugation, but like the indepen- 
dent generations of Infusoria observed by Maupas represent when 
collectively considered cycles of development, usuall}^ having first 
asexual zoons una1)le to perpetuate themselves by conjugation, 
tlien sexual zoons. and llien either these or their descendants or 
associated moditied forms present the degenerative extreme of the 
cycle. ^ 
If, now, the Haeckelian terms anaplasis for the young and adoles- 
cent stages, metaplasis for the adult, and the term used farther on 
for senile stage, paraplasis, be adopted, it is obvious that the term 
growth applies only to the connections that exist between these 
three ages and the building up and decline of the agamic cycle. 
In other words the branch of science dealing wath growth is essen- 
tially ontogenetic. Over and above the physiology of cellular 
metabolism, it can also be appropriately applied to the morphology 
of intra-cellular increase or anabolism, and cellular development 
or catabolism, and the jdienomena resulting from the alternating 
is a zooii of tlie Poriferaor a spoiinozoon, but it isconfiisinfj,- to use "zoou" for a single 
protozoan. This is niorphically a free cell and iu allusion to the common mode of 
multiplication I have descriptively styled it an autotemnon. Thus a single free proto- 
zoan is an autotemnon and also its descendant from the single tissue cell in tlie meta- 
zoan, but the colonies of Protozoa such as those studied by Maupas, or those held 
together as in Vorticella, are alone comparable with a zoou of the Metazoa. Individual 
even if defined in a very broad .sense, means an independent being tliat cannot be arti- 
licially divided without at least tlie temporary loss of its individuality and is sometimes 
used in a modified sense even for inorganic bodies. Person as used by Ilaeckel and 
others is equally objectionable since it can be properly applied only to individuals 
having a certain character. The personality of God. or of a man is an appropriate 
expression but the personality of a polyp conveys an essentially erroneous idea so far 
as our existing knowledge of such animals extends. Zooid can also be used in con- 
nection with zoou but it is someAvhat less definite, meaning really, like a zoon. 
1 See remarks on Maupas's researches below under "The cycle." 
