332 KOREN AND DANIELSSEN ON THE 



water and perfectly fluid, so that the embryos could easily be 

 extracted from it. In another capsule there were but six em- 

 bryos, four of which were well formed. 



We began then to form a conception of the import of all these 

 facts ; but they seemed to us to be so extraordinary, that for a 

 long time we did not venture to put confidence in our observa- 

 tions — so different were these results from all that had hitherto 

 been seen with respect to the development of Mollusks, and even 

 from all known physiological phaenomena. But the attentive 

 study of what went on under our eyes at last cleared away all 

 our doubts, and led us to dispute a law generally admitted and 

 based upon a great number of facts. In fact, we had before us 

 a mode of development which required for its proper under- 

 standing much new investigation ; and it appeared to us to 

 be indispensable to follow out these singular phaenomena in 

 neighbouring genera, in order to see if, towards the limits of this 

 zoological group, we should find them disappearing ; an anticipa- 

 tion which, as we shall see by and by, has been fully justified. 



But let us first trace out these phaenomena in the Buccinum, 

 and we shall find them surprising enough ; for we shall look 

 in vain in a fecundated ovum, for any of those changes which 

 in ordinary cases take place during its development, in virtue 

 of the well-known law of yelk-division. We see no grooving — 

 no cell appears ; in a word, the interior of the ovum remains 

 without alteration ; on the other hand, external to it we observe 

 active alteration. The excessively viscous albuminous fluid 

 collects and, so to speak, glues together the ova, which were 

 primarily separate, uniting them into bunches ; subsequently 

 the mass in which they were immersed, from being viscous, be- 

 comes as liquid as water ; and it is then that we first perceive 

 traces of activity in the ovum itself. Its external membrane 

 bursts in certain places — the yelk becomes diffused, and a mem- 

 brane, destined to circumscribe the developing individual, is 

 produced around each bunch of ova; between these bunches 

 we see many isolated ova, which seem excluded from this organic 

 process which gives rise to embryos. We do not know if these 

 isolated ova die at once, or undergo a further imperfect develop- 

 ment ; but in any case they are beings, whose existence is but 

 ephemeral. As soon as the grouped ova are invested by their 



