ANTIIOZOA IIYDROIDA. 15 



seasons only, were believed to be the fruitful females.* Ob- 

 servations to fortify these novel views have been published by 

 several naturalists, and they have been adopted with ardent 

 zeal by M. Loven. He found that in the Ooryne the sexes 

 were marked by outward characters, the females having no 

 tentacula ;-f- an observation which has been confirmed by 

 Quatrefages and Van Beneden, who add that, in an allied 

 genus, the oviferous individuals are without any oral aper- 

 ture. j These, and other observations to the same purport, 

 are correct; but, as Van Beneden appears to us to have 

 proved, they have been misinterpreted, and will not support 

 the conclusion that has been deduced from them. The semi- 

 nal animalcules detected in some species are granular bodies 

 connected with the circulation ;§ and the misnamed females 

 which have been described as pullulating from the body of 

 another polype, or nestling in the ovarian vesicles, are young 

 polypes incompletely developed, but which contain ova or 

 buds before they have attained their full growth. || It is a 

 disregard of the fact that the young can develop ova that has 

 led to this sexual theory, which, with Van Beneden, we 

 consider to be erroneous ; but at the same time it is not to 

 be denied that, in almost every cluster of every species, some 

 individuals will be observed to be barren while others are 

 loaded with gemmules or ovigerous vesicles, and in the latter, 

 the tentacula of the polypes, or the branches of the polypidom, 

 are occasionally more or less defective and atrophied. 



This order of zoophytes is propagated by buds or gemmules 

 and by eggs. By the former the polype extends its individual 



* I have not seen any work of Ehrenberg's in which this view is given, but I have 

 gathered my statement of it from other works. In the " Corallenthiere des rothcn 

 Meeres," published in 1834, Ehrenberg says of these zoophytes : "Androgyna, nun- 

 quam sexu discreta ; interdum alia unius speciei individua semper sterilia, alia ovipara 

 {Hydrae, Corynae, al.), apparatu femineo valde distincto, masculo nondum repcrto." 

 p. 31. 



t Microscopic Journal, i. p. 107. 



J Quatrefages in Ann. des Sc. Nat. xx. p. 233. — Van Beneden sur les Tubulaires, 

 p. 63. Ann. Nat. Hist. xv. p. 248. 



§ Van Beneden sur les Tubulaires, p. 28-9, and p. 33 . sur le sexe des Ano- 

 dontes, p. 7, 8. 



II Sur les Tubulaires, p. 25. Also Ann. Nat. Hist. xv. p. 245. 



