Fecundation of the Ovum. 297 



afterwards form the nuclei of the embryonal cells. We shall not 

 enter uj)on these details, as tiiey are rather too romantic. We 

 cannot in any case attach the least credence to them, as long as 

 Kebcr does not inform us how he succeeded in determining the 

 ])criod at which his supposed spcrnuitozoid entered into the 



Keber's discovery is not confined to this. Following in Barry's 

 ste])s, he pretends to have seen the micropyle in the ova of the 

 Rabbit, and followed the spermatozoids which had just lodged 

 there. His drawings, howe\er, do not agree very well with those 

 of the English anatomist, and it is a curious cu'cumstance that 

 he states that he met with the ovules not only in the uterus and 

 oviduct, but also and csi)ecially in the abdominal cavity, in the 

 mesentery, &c. He has even found them sometimes in such 

 numbers in tlie cavity of the body, that he inquires whether it 

 is not probable that these so-called ova may at a later period 

 reach the uterus by some unknown migration (!). Astonishment 

 will cease when we learn that Kebcr never saw the ovule of the 

 Rabbit, as has since been proved by Rischoff*. These so-called 

 eggs of the Rabbit, covered with vibratile cilia on their whole 

 inner surface, arc a species of hydatic vesicles, furnished with a 

 tubular peduncle, which have been described by Remakf under 

 the name of vibratile vesicles {IJ'imperblasen). They are pretty 

 frequently mot with on the mesogastrium and mesometrium of 

 the Rabbit, as well as in the lobes of the thymus gland ; and also 

 in the Cat. They are, moreover, found before, during and after 

 the rutting season, and both in young and old individuals. This 

 last mistake is sufficient to detract remarkably from the value of 

 Keber's other observations, especially as he appears to attribute 

 a very peculiar importance to his discovery of the micropyle in 

 the Rabbit, since he has the modesty to compare this discovery, 

 not due to chance, but supported by induction, to that of the 

 planet Neptune by Lcverrier and Gallc (! !). And yet Keber's 

 conscience was not satisfied as to his fact, for in speaking of 

 these vibi-atile vesicles, he exclaims, " And if these were not eggs, 

 I should be glad to know what they were !" 



Keber's work, notwithstanding all its faults and errors, could 

 not but contain some truths, amongst which we may give the 

 first place to the prediction expressed in his preface, that this 

 volume would astonish many people, and would be arranged by 

 many amongst the curiosities of science. This is a position 

 which it has since attained. Nevertheless, if it had only the 



* Widerlegiiiig des von Dr. Kebor bei den Najaden, nnd Dr. Nelson 

 bei den Ascariden behaupteten Eindringens der Spermatozoideu in das Ei. 

 Gicsscn, 185^5. 



t Mailer's Arcbiv, 1841 & 1854. 



