_Phil_.--It is now ten years since I first visited this spot. I was exceedingly anxious to see the proteus, and came here with the guide in the evening of the day I arrived at Adelsberg; but though we examined the bottom of the cave with the greatest care, we could find no specimens. We returned the next morning and were more fortunate, for we discovered five close to the bank on the mud covering the bottom of the lake; the mud was smooth and perfectly undisturbed, and the water quite clear. This fact of their appearance during the night seemed to me so extraordinary, that I could hardly avoid the fancy that they were new creations. I saw no cavities through which they could have entered, and the undisturbed state of the lake seemed to give weight to my notion. My reveries became discursive; I was carried in imagination back to the primitive state of the globe, when the great animals of the sauri kind were created under the pressure of a heavy atmosphere; and my notion on this subject was not destroyed when I heard from a celebrated anatomist, to whom I sent the specimens I had collected, that the organisation of the spine of the proteus was analogous to that of one of the sauri, the remains of which are found in the older secondary strata. It was said at this time that no organs of reproduction had been discovered in any of the specimens examined by physiologists, and this lent a weight to my opinion of the possibility of their being actually new creations, which I suppose you will condemn as wholly visionary and unphilosophical. _Eub_.--From the tone in which you make your statements, I think you yourself consider them as unworthy of discussion. On such ground eels might be considered new creations, for their mature ovaria have not yet been discovered, and they come from the sea into rivers under circumstances when it is difficult to trace their course. _The Unknown_.--The problem of the reproduction of the proteus, like that of the common eel, is not yet solved; but ovaria have been discovered in animals of both species, and in this instance, as in all others belonging to the existing order of things, Harvey's maxim of "omne vivum ab ovo" will apply. _Eub_.--You just now said that this animal has been long an object of attention to you; have you studied it as a comparative anatomist, in search of the solution of the problem of its reproduction? _The Unknown_.--No; this inquiry has been pursued by much abler investigators: by Schreiber and Configliachi; my researches were made upon its respiration and the changes occasioned in water by its bronchia. _Eub_.--I hope they have been satisfactory. _The Unknown_.--They proved to me, at least, that not merely the oxygen dissolved in water, but likewise a part of the azote, was absorbed in the respiration of this animal.