DEVELOPMENT. 15 
of propagation by gemmation was long supposed among Radiata to be an especial privilege 
and distinction of the true zoophyte; but the march of discovery and the revolutions of 
science, do away with such artificial distinctions, though the recognition of them in their time 
gave no small impulse to the onward progress which was eventually to destroy them. The 
discoveries of Sars, Dalyell, Loven, Wagner, Van Beneden, Dujardin, and Steenstrup have 
changed the face of this section of creation seriously, and prophetically indicate many coming 
changes. It is the duty of the philosophical zoologist to keep pace with the railroad speed 
of modern research, and whilst conservative of all past statements, as yet insufliciently 
combated, never to hesitate to cast away preconceived notions and old teachings the moment 
they are clearly shown to be untrue. “Free and unprejudiced spirits will neither antiquate 
truth for the oldnesse of the notion, nor slight her for looking young, or bearing the face of 
novelty.”* 
The polypes of the genus Coryne and its allies, of Zubularia and Eudendrium, and of 
the beautiful Corymorpha, send forth at certain times bud-like bodies, more or less sym- 
metrically arranged around their heads. These bodies have long been recognised as 
young animals, though not until very recently was it known that the creatures so produced 
bear no resemblance to their parents, but were indeed true Medusz, and not polypes, which, 
however, in their turn produced eggs capable of producing polypes. Such appears to be the 
true interpretation of the phenomenon—a part of the justly celebrated theory of alternation of 
generations which has originated in the imaginative mind of Steenstrup. On the bearing of 
such discoveries on the better classification of the Radiata, I shall have to make a few remarks 
presently. Now, among the dcalephe, no such reproduction by gemmation in the manner 
of the Coryne was known until discovered in 1836 by Sars, who had previously been the 
first to announce the surprising fact of the intermediate S¢robi/a condition of the higher 
Medusz, a discovery made independently and simultaneously in Scotland by Sir John Graham 
Dalyell. 
The discovery made by Sars was that certain forms of naked-eyed Meduse multiply 
their species by means of gemmation, the buds being produced either from the walls of the 
peduncle or stomachal proboscis, or from the surface of the ovaries, the former mode occurring 
in the “ Cyt@is octopunctata’ (Lizzia octopunctata, Mihi), the latter in Thauwmantias multi- 
cirrata. In both cases, the new individuals were not different from, but similar to, their 
parents, and, in one instance, provision seemed to be already made in the new-formed individuals 
for continuing to propagate by the same mode other individuals similar to itself. The full 
account of these remarkable and highly important observations, illustrated by excellent figures, 
is contained in the lately published ‘ Fauna Norvegica,’ a most admirable work, by one of the 
greatest of living investigators of life in the sea. I shall extract it hereafter when describing 
the Lizzza, in the second part of this essay. At present I shall cite the summing up given by 
Sars, and his notice of the phenomenon as it occurs in the 7haumantias. 
“We now recognise a mode of procreation and development hitherto unknown among the 
Acalephe. From a certain part of the body (in this instance the tubular stomach, hanging 
independently in the cavity of the disk) roundish knobs grow forth from the upper towards 
the lower part, which gradually assume the shape of a bell, by opening themselves at the free 
* Henry More. 
