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Show 574 MR. G. A. BOULENGEB ON THE [Dec. 2, Cambridgeshire, and Stow Bedon and between Thetford and Scoulton in Norfolk), and generally regarded as introduced from France and Belgium, belongs to the Italian form, B. esculenta lessona; and concluded by expressing the hope that descendants of the typical B. esculenta, which was introduced in great numbers into Norfolk by Mr. G. Berney forty years ago, would be discovered. Through the kindness of Lord Walsingham, W . Amhurst Amherst, Esq., M.P., and Geo. E. Mason, Esq., who took an interest in the question, I have received much information and additional material this summer; and, what is more important, the typical B. esculenta has been found in or near some of the places where specimens were turned out by Mr. Berney, but where they remained unnoticed, or were confounded with the form lessona, the introduction of which is clearly of a much older date. The result is the addition to the British fauna of a new form of Frog. If I say " form," and not "species," it is because the limits of these forms are difficult to establish when the whole Palaearctic range is taken into consideration ; but so far as England is concerned, the two forms are as distinct as many generally accepted " species." I may even add that, according to the definition of the genera Bana and Pyxicephalus (Hoploba-trachus) admitted by many authors, Bana esculenta lessona would fall into the latter; but I have elsewhere expressed m y objections to the validity of the genus Pyxicephalus. Soon after the publication of m y note in the ' Zoologist,' I received from Lord Walsingham seven specimens from Stow Bedon ; and on July 29 I had the pleasure of accompanying his Lordship on an excursion to that place, on which occasion twelve more specimens were captured. The Frogs were very abundant at Stow Bedon, in small pools and pits, which, owing to the excessive drought, contained but little water. They did not indulge in their sonorous croaking on the occasion of our visit, and no tadpoles or spawn were to be seen. However, one full-grown tadpole was dredged from the bottom of a pit, but was so much injured that I could not preserve it. I was rather surprised to find that none of the specimens presented that beautiful green colour which is usual in B. esculenta ; ail were olive-brown, spotted and marbled with black, and provided with a pale yellow or pale green vertebral line ; all had the enormous metatarsal tubercle. This accounts for the fact for which I always was at a loss to find an explanation, viz. the silence of the first discoverers of the Edible Frog in Cambridgeshire as to the green colour which, among other characters, so well distinguishes that species from the Common Frog. B. esculenta lessona, as occurring in England, is never green. Lord Walsingham informed me that he was making inquiries among the people of that neighbourhood as to how long the Frogs had lived there, and that he had been assured that their existence could be traced as far as sixty years back. Lord Walsingham also inquired of Mr. G. Berney whether the Edible Frog had maintained its existence in Hockering, and was informed that for years past not one had been seen anywhere in that neighbourhood. On a request made by Lord Walsingham to Mr. Amhurst A m herst, I received from that gentleman on August 9 two fine living |