538 REPORT ON ZOOLOGY, MDCCCXLIV. 



of Polype. The young Polypes correspond in aspect and in 

 their motion with Acalephse, whence a near relationship 

 between these Potypes and the latter class of Zoophytes is 

 deduced." 



Minute corpuscles, covered with vibratile cilia, which 

 swam about in water in which Sertularise and Campanularise 

 were kept, were regarded as ova by Peach (Institut, 1843, 

 p. 454), but were, on the other hand, declared by Forbes 

 to be Medusa-embryos. 



Kolliker (Froriep's n. Notiz. Nr, 534, p. 81) observed, in 

 Sertularia Cavolini, that the young, on quitting the ovarian 

 vesicles of its polypidom, possessed a medusiform figure, 

 which enables them to swim about freely in the water, by 

 the contractions of their discoid body. 



From a comparison of the various observations and 

 opinions of the older and more recent naturalists, respecting 

 the modes of increase of the Polypes, which has been under- 

 taken by Krohn (Miiller's Archiv, 1843, p. 176), it appears 

 that the figure of the females, their connexion with the 

 polypidom, persistent till dissolution, their discharging them- 

 selves, and the period of the development of the ova, vary to 

 an extraordinary degree in each of the different species. 

 Krohn describes the various medusiform, free swimming 

 animalcules belonging to Syncoryne and Campanularia as 

 the females of those Zoophytes. 



E. Forbes (Report of the British Association, 1844, Notices, 

 p. 68, and Annals, xiv, 1814, p. 385), in a paper on the 

 " Morphology of the Reproductive System of the Sertularian 

 Zoophyte, and its Analogy with the Reproductive System of 

 the Flowering Plant," compares the formation of the repro- 

 ductive organs in the Sertulariadre to that of the flower in 

 plants, inasmuch as in the former an ovigerous vesicle is 

 produced by the [ideal] metamorphosis of the polypidom 

 and its branches, in the same way that the flower arises 

 from a metamorphosis of the stem and its leaves. At the 

 same time he proposes to classify all Zoophytes in the four 

 following orders : (1) [Those which present the ovaries in 



