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Show 1899.] MR. L. A.BORRADAILE ON THE PAGURINE LAND-CRABS. 937 phractus, a Python, 3 Cgclanorbis senegalensis, 2 Hinged Tortoises, some Chameleons, aud a Serval Cat were brought home alive. Since m y return to England, I have definitely decided that the eggs and larva? obtained are not those of Polypterus. I have, however, I believe, learned enough about the habits of Polypterus to encourage me to make a second attempt next year to obtain the developmental stages. In conclusion, I wish to thank the Society for lending me influence and support, without which the little that has been done by this expedition could not have been accomplished. 2. A Note on the Hatching-stage of the Pagurine Laud-crabs. By L. A. B O R R A D A I L E , M . A., F.Z.S., Lecturer in Natural Sciences of Selwyn College, Cambridge. [Received October 12, 1899.] The life-history of the Land-crabs of the family CcenobitidaB is one to which considerable interest attaches, and of which, at present, nothing appears to be known. The family comprises the genera Birgus and Ccenobita, the robber- or coconut-crab and the land hermit-crabs, all of which have given up a sea life for one on land. It need hardly be remarked that changes in habitat, particularly from sea to land or fresh water, have frequently necessitated tbe suppression of larval stages in the life-history. Among Crustaceans the instances of the cray-fishes, the ditch-prawn (Palcemonetes varians), the freshwater crabs (Potamon), and at least one species of land-crab (Gecarcinus) come at once to mind. The possibility was thus suggested that the land-pagurines might also have lost the whole or a part of their larval life, and leave the egg in something like the adult condition. On the other hand, it had to be borne in mind that some species of land-crabs and all the strand-crabs (Ocypoda, &c.) retain the habit of setting free zosea-larvse in the sea, where they pass through their earlier stages. It was probably with these considerations in his mind that von Willemoes-Suhm, when, in October 1874, the ' Challenger' arrived at Zamboanga in the Philippine Islands, wished to investigate the development of the robber-crab from the egg. Unfortunately the time of year rendered it impossible for him to do this, but he'was told by an " intelligent native" that the young were born resembling the parent. This statement has since been accepted in a tentative manner by certain text-books, in spite of the fact that the small size of tbe eggs (and, indeed, of the female genital opening) made it improbable that the development was a direct one, depending on food-yolk. As for the statement of the |