DR. ALLMAN ON THE ANATOMY AND PHYSIOLOGY OF CORDYLOPHORA. 377 
bodies, but never detaching themselves from the parent, and always after a time filled 
with ova or spermatozoa*. 
In Camipanularia bodies of highly developed mediisan conformation are produced, 
generally in considerable numbers, in external capsules situated on parts of the poly- 
pary always at a distance from the terminal polypes. When arrived at a certain 
degree of maturity, they escape from the capsule and swim freely through the 
surrounding water. In the capsules of Campanularia another kind of body has been 
also observed, in which the medusan structure is less complete, and these, after dis- 
engaging themselves from the cavity of the capsule, continue attached to its mouth, 
never becoming entirely free; while a third kind of bodies, corresponding with the’ 
fixed sacs of the Tuhulariadce, is also borne in the capsules of Campanularia f. 
In some instances the free medusoid bodies of the Tuhulariadce have been found 
to contain ova, as has been observed by Wagner:[: in a tubularian polype from the 
Adriatic, apparently referable to Hijdractinia, Van Beneden, by Loven^ in a Syn- 
coryne, and by Dujardin|| in another species of Syncoryne, whose medusoid was seen 
to produce ova in the thickness of the stomach-walls. The less perfectly developed 
medusoids which remain attached to the mouth of the capsule in Campanularia have 
also been observed to contain ova as noted by LovEN«[y ; while the previous observation 
of Lister**, who saw multitudes of moving bodies escaping from these medusoids, 
is possibly also an instance of a similar phenomenon, though the form of the moving- 
bodies as described by Lister leaves a doubt of their being truly embryos ; they are 
probably spermatozoa, and then Lister’s medusoids would be males; a view sup- 
ported by Shultz’s ft recent observation, that these attached medusoids of Campanu- 
laria sometimes contain spermatozoa instead of ova. 
Now m Cordylophora I have never witnessed the production of medusoids, but I 
think nevertheless that it will be easily seen that the reproductive capsules of this 
genus have essentially the same organization as the medusoids of the marine genera. 
These capsules in an advanced stage exhibit but little of a medusoid conformation, 
but at an earlier period of their development, as we have just seen, they present us 
with an organized sac having a hollow central and fleshy column projecting into it 
below, and furnished with a system of branched canals which are developed on its 
walls, and communicate at their origin with the cavity of the central column. In 
this structure we can have no hesitation in recognising a true medusoid type ; the 
organized cellular sac is homologous with the disc of the Medusa, the central fleshy 
column wall represent the peduncle or proboscidiform stomach, while the system of 
branched tubes will correspond to the gastro-vascular canals|:{:. It is true that neither 
t Vide infra, p. 378. 
t Wagnek in the Isis, 1833. Heft iii. 
* See Kkohn in Muller’s Archiv. 
§ Loven in Wiegmann’s Archiv, 1837. 
II Dujaedin in Ann. des Sci. Nat. 3“^ ser. tom. iv. 1843. % Loven, /. c. 
** Lister in PhUosophical Transactions, 1 844. tt Shultz in Muller’s Archiv, 1851. 
n The ramified tubes of the reproductive capsules must, I think, be also assumed as homologous with the 
tentacles of the terminal polypes. The tentacles of a hydroid polype will thus find their homologues in the 
gastrovascular canals of a medusa. 
3 D 2 
