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Show 12 Mil. A. MURRAY ON TBE STERLET. [Jan. 3, of being placed upon record. The gentleman who was intrusted with the duty of procuring the ova, and who undertook a journey ot 900 miles to the Wolga to get them, was Dr. Knoch, an experienced Russian pisciculturalist and able ichthyologist. I published his account of his journey in the papers I have above alluded to. In addition to the practical details and narrative there contained, he made the following observation regarding the micropyle of the ovum :- "The assertion made by Professors Owsjanikow and Wagner and Mr. Kowalewsky, and contained in the Bulletin of the Academy of Sciences of St. Petersburg for June 29th, 1869, viz. that 'the mi-cropyle- apparatus consists of seven micropyle openings grouped round a pole, of which one is situated in the centre, whilst the remaining six surround it in the form of a circle,' is not correct and is contrary to all previous experience. Indirect opposition to the micropyle structure of these gentlemen, and in most perfect harmony with m y observations on the eggs of other fish, was the proof which I had later an opportunity of giving, that in the eggs of the Sterlet, as well as in those of all other red fish (Acipenserini), the micropyle consists of a (towards the outside) funnel-shaped, widened and simple canal, and not by any means, as those savants assert, composed of several (seven) openings." It is satisfactory to have this distinctly settled; for it certainly seemed a most unnecessary superfluity, whether of obstacles or openings, to have seven instead of one. The other point is still more remarkable and unexpected. Dr. Knoch says, " Allow me to draw your attention to one very interesting circumstance which surprised us during the development of the Sterlet. Accustomed to the toothless jaw of the Sterlet and Sturgeon in a more advanced stage, we were not prepared to find teeth in the early stage of these fishes. W e found, however, immediately behind the lips of the Sterlet just escaped from the egg, eighteen pretty strong and curved teeth ; and when in their lively movements in the water they sometimes fall upon each other with their teeth, it is no easy matter to separate them." Not being aware of this remarkable fact when I had the young Sterlets in m y hands, I did not think of examining them in relation to it; nor did I observe any thing like them seizing each other; but my period of observation was necessarily very limited, m y great anxiety being to shorten the period they were in my hands as much as possible, and get them safe into the keeping of nature in a flowing stream. I had, however, preserved two or three young specimens in spirits, and I have endeavoured to verify Dr. Knoch's observation upon these, but without success. M y failure to do so, however, says nothing against the accuracy of his observation ; for we all know how the tissues alter when preserved iu spirits, and how much more difficult it is to make any delicate anatomical investigations upon specimens which have been so preserved. Dr. Knoch adds that the barbies which characterize the Acipenser tribe are, in the young Sterlets, not fringed on the inside. I should say that, although this seems to be the rule, in one under |