228 
SIEBOLD, ON PARTHENOGENESIS. 
of plants, a list of which, with the observer of the phe- 
nomenon, we subjoin : 
ChABACEtE. 
Char a crinita, A. Braun. 
Cannabine^. 
Cannabis sativa, Naudin. 
Chenopodiace^. 
Spinacea oleracea, Le Cocq, 
EUPHOEBIACE^. 
Coplebogyne ilicifolia^ J. Smith. 
Mercurialis, species, Naudin. 
Anacabdiace-zE. 
Vistacia Narhonensis^ Tenore. 
Pistacice species, Bocconi. 
Cucuebitace^. 
Bryonia dioica, Naudin. 
Datisce^. 
Datisca cannaUna, Fresenius. 
Although this phenomenon looks, at first sight, so ex- 
ceptional, a little reflection will show that it is in accordance 
with the general plan of the growth and reproduction of 
organized beings. In both the vegetable and animal king- 
doms there are two plans of procedure, — one for the repro- 
duction of the tissues of the same individual, in which single 
cells or parts resembling each other are produced. This is 
simply growth, and goes on whether the particular plant or 
animal forms one mass, or splits up into single cells or larger 
parts. This process we may call Homogenesis. In plants it 
produces buds (phytoids) , bulbilli, bulbs, sporules, or any other 
parts like or unlike to the stock or part on which it is borne 
(isophytoids and allophytoids) . In animals it produces buds 
or gemmae (zooids), which, like the homologous parts in 
plants, are either like or unlike their parent-buds (isozooids 
and allozooids) . Here will be found the nurses" of Steen- 
strup, the " agamazooids" of Lubbock and Huxley, and the 
" virgin mothers" of Owen. The other plan may be called 
Hetero genesis. Here a new series of homogenetic actions is 
initiated. For this process two cells are required — ^a sperm- 
cell and a germ-cell. In the plant the phytoid changed in 
its form bears the sperm- cell and is called a stamen (andro- 
phytoid) , or the germ-cell and is called a pistil (gynophytoid) . 
These are combined, and we have a hermaphrodite flower 
(androgynophytoid) . In the homologous parts in the animal 
kingdom we have separate male animals (androzooids) and 
female animals (gynozooids), and the two sexes combined in 
hermaphrodite animals (androgynozooids) . By this mode 
of viewing the phenomena of Parthenogenesis, it will be seen 
