Mr. C. C. Babington on some species q/'Epilobium. 311 



made upon the ova of the Batrachia by many authors * have not 

 led to the discovery of the micropyle in them ? 



3. Penetration directly into the naked vitellus. It is certain, 

 in fact, that the mode of origin of the ova described by Meissner 

 in Mermis albicans, M. nigrescens, and several Ascarides, is not 

 general even amongst the Nematoid worms. A great many ova 

 only obtain an envelope at a very late period, and are probably 

 fecundated before they possess one, so that they do not require 

 the presence of a micropyle. Meissner himself has seen the 

 spermatozoa penetrate directly, and in crowds, into the ova of 

 the Earthworm, at a period when they are completely destitute 

 of an envelope. As regards these, Meissner supposes that they 

 originally possess a membrane which disappears before fecunda- 

 tion. This is very possible, as we know that a similar disap- 

 pearance takes place, although at a later period, with the vitel- 

 line membrane of the ova of Gasteropoda and Insects (Rathke, 

 KoUiker, Zaddach, Leuckartf). 



[To be continued.] 



XXV. — On some species q/" Epilobium. 

 By Charles C. Babington, M.A., F.R.S. &c. 



[Concluded from p. 247.] 



We will now turn our attention to the species allied to E, 

 alpinum, which present some difficulty, from there being pro- 

 bably two plants which pass by that name. Of this Dr. Godron 

 was well aware when preparing the account of this genus for the 



* Swammerdamm, Biblia Naturae. Leeuwenhoeck, Arcana Naturae. 

 Rcesel, Hist. Nat. Ranarum nostratium; Numberg, 1758. Spallanzani, 

 Diss, relatives a FHist. Nat. des Animaux et des Vegetaux, 1789. Pre- 

 vost and Dumas, Ann. des Sci. Nat. tome ii. Rusconi, Developpement de 

 la Grenouille commune; Milan, 1828; and Amours des Salamandres, 1821. 

 Baer, Lettre sur la Formation de I'CEuf, 1829; Repertorium; Miiller's 

 Archiv, 1834. Reichert, Entwickelungsleben im Wirbelthierreich ; Berlin, 

 1840. Vogt, Untersuchungen iiber die Entwickelungsgeschichte von der 

 Geburtshelferkrote ; Solothurn, 1842. Bell, British Reptiles. Newport on 

 the Impregnation of the Ovum in the Amphibia, Phil. Trans. 1851 and 

 1853. 



t We might add to these a fourth mode of fecundation, if we admitted, 

 with Remak (Miiller's Archiv, 1854), that the spermatozoa are only 

 destined to transport a substance serving to effect fecundation {die Tr'dger 

 einer samendhnlichen Substanz). This substance being capable of passing 

 through the little canals of the external membrane of the ova of Fishes, it 

 would not be necessary that the spermatozoid itself should penetrate into 

 the ovum in these animals. But we are already acquainted with the 

 micropyle in many fishes, and it will probably be discovered in the others, 

 which renders this theory very useless. 



