88 CLASSIFICATION OF MEDUSA. 
phytons comprising the first bud or plumule. A series of similar buds may be produced 
until one of different aspect is developed, composed of a generation of altogether different 
individuals, through whose agency the foundation of a new series of generations is laid in the 
formation of the ovum or seed. Whether we style the members of one generation nurses, or 
call them all by the same name, does not matter so far as the fact and law of an alternation 
of generations is concerned. 
I see no reason therefore to dissent from the theory of Steenstrup; it is the simplest and 
most intelligible, as well as most original expression hitherto offered of the astonishing facts 
which he was the first to generalize. Granting it, we can no longer adopt the usually 
accepted classification of Radiate animals, nor separate them into Echinodermata, Acalephe, 
Zoophyta, and Sponges, as so many distinct and equal orders; but must unite the dealephe 
with the Zoophyta, excluding from the latter the Bryoxoa which are polypoid Zunicata. 
The Acalephe or Arachnodermata must undergo reconstruction, for the Polypes cannot even 
be regarded as forming a primary division when united with the usual members of this great 
section. They evidently form part of a sub-class with the Discophore, equal to the sub- 
classes, Ciliograda, Cirrhigrada, and Physograda. The Discophore must again undergo 
subdivision into orders. The Anthoxoa will stand first, next the Steganopthalmata, then the 
Gymnopthalmata, and lastly the Hydroida. That the Anthoxoa are intimately related to the 
Medusz is evident to any unprejudiced naturalist who has studied the structure of Lucernaria, 
or of the Actineade, especially of any floating form of the last tribe, such as the Arachnactis 
of Sars. The close affinity of these tribes has been excellently treated of in an Essay by 
Drs. Frey and Leuckart, who, after comparing organ with organ in the Anthoxoa, the several 
usually received orders of Acalephe and the Polypes, observe, in conclusion, that these various 
tribes ought no longer to be placed apart in a natural system. ‘They rather go towards 
constituting a larger section, having one common type of structure—a type chiefly charac- 
terised by the peculiar arrangements of the viscera and the stomachal cavity.” They 
propose to designate such division by the name of COLENTERATA.* 
Even among the animals figured and described in this Monograph, we see abundant 
evidences of the close affinity of the Medusze, on the one hand, with hydroid polypes ; on the 
other, with the Anthozoa. The Steenstrupie are in all probability Medusa-generations of some 
corynoid polype, yet, through Zuphysa, they are intimately related with Sarsia, and through 
Sarsia with Slabberia, whence the affinities upwards are easily traced. The Zurris digitahs, 
on the other hand, closely reminds us of an Actinea; so nearly, that when I first found a 
specimen, I mistook it for an animal of that genus. 
Thus, in the end, we revert, curiously enough, to the views of the affinities of these 
animals proposed by Aristotle, who plainly included, under the designation of axkaAngn, both 
Actinee and Meduse ; not from any vague guess, or in compliance with the popular recognition 
of their resemblances, but from a careful study of their structure and habits, as the varied 
notices of them preserved to us in the first, fourth, fifth, eighth, and ninth books of the ‘ History 
of Animals,’ prove beyond question. 
* Frey and Leuckart’s Beitrage, p. 38. 
