| Abstract/Notes | One of the most widely quoted but least common Chalk ammonites is Ammonites navicularis Mantell, which has been the subject of a very careful paper by the late G. C. Crick. Judging by the literature, however, this species is still generally misunderstood, and inquiries from correspondents are partly responsible for the present note. There is no doubt that widely different forms have been included in A. navicularis, from Sowerby's time (1827) down to the present (e.g. Collignon, 1931), and I have on previous occasions separated, with new names certain forms wrongly attributed to this species by Sharpe (1857), Guéranger (1867), and de Grossouvre (1912). But although a good deal remains to be done, without figuring typical specimens and without having material for comparison from India, Portugal, and Madagascar, it is not advisable to express opinions on the ammonites figured as A. navicularis by yet other authors, e.g. Stoliczka (1865), Choffat (1898), or Boule Lemoine, and Thévenin (1907). |
|---|
