Letter, Arthur Tindell Hopwood, British Museum (Natural History), Cromwell Road, London, to Percy George Hamnall Boswell, Royal School of Mines He is glad that Boswell has no objections to Hopwood's proposal for making stage-names for the East African Pleistocene. He will try to find out what Solomon thinks about Kaiso. Kaiso is undoubtedly Pleistocene. There are two elephants, as at Kanam, the more advanced not much more primitive than that from Olduvai. There is also a horse, probably from the Quagga group of Zebras. Hippos are first known from the lignites of Casino and continue through the Astian, Villafranchian and Pleistocene. The disappearence of the small one is one of the most striking things in the change from Kaiso to Oldoway times. If he had the Pleistocene elephants he would not place so much stress on the hippos. He correlates Kagur and Rawi with Kanam. Such scraps of elephants as he has from Kagur appear to be the same as fossils from Kanam. Large and small hippos are found at all three localities but beyond this he cannot go. Kent is due here on Thursday afternoon and it would be pleasant to see Boswell too. He thinks that Kent wishes to discuss the correlation of the East African deposits. 17 March 1936