338 
PRACTICAL NOTES ON “ HETEROGrENESIS,” 
A REPUTED FEATURE OF SPONTANEOUS GENERATION. 
By the Rev. W. H. DALLINGER, V.P.R.M.S. 
[PLATES CXXXIX. AND OXL.] 
T HE doctrine of “ spontaneous generation ” is declared by its 
principal advocate* to involve not merely the origin of living 
forms from not-living elements, but also the origination from 
living beings, more or less complex in organisation, of other 
living units wholly different from themselves, and having no 
tendency to assume or revert to the parental type. This means 
briefly that one organised form may, by the operation of some 
occult laws, produce another organised form wholly unlike itself, 
and which may be not only of a different genus, but of a dif- 
ferent order of a different class — nay, probably altogether of a 
different kingdom. This is an assertion of caprice in biological 
laws. Their action is uncertain. True, these remarkable phe- 
nomena are not at present asserted of the more easily accessible 
and highly developed organisms ; but it may be instructive to 
note that if they were so applicable it would admit, for example, 
of a humming-bird being hatched from a snake’s egg, or a 
gorilla being born from a kangaroo ; for neither of these instances 
is more startling than the alleged transformation of Euglenae 
and Chlorococcus directly into — rotifers ! Yet not only this, 
but many other things equally as remarkable, are sanctioned 
and asserted by Dr. Bastian ; and the credence of biologists is 
asked for these affirmations, with as little apology or hesitation, 
as for the fact that a tadpole is the precursor of a frog, or a 
chrysalis of a butterfly. 
This of course gives much greater complexity to the hypo- 
thesis of spontaneous generation ; but at the same time it gives 
it character. It is at least unique. 
“ The Beginnings of Life.” Dr. H. G. Bastian. Yol. i. p. 244. 
