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Show 936 AN EXPEDITION TO THE GAMBIA. [Nov. 28, In the open plains, where clumps of tall dead grass were shaded by a few trees, one might generally count on starting a Konko-tong (Cobus kob), some Gazelles, or a Harnessed Antelope. The smaller solitary Antelopes were usually found in pairs. Enquiries were instituted everywhere as to the existence in this region of a Zebra, but I could hear nothing of it. The horns either collected by m e or from the natives included those of 9 species -.-Bubalis' major, Damaliscus korrigum, Cobus unctuosus, Cobus kob, Cervicapra redunca, Hippotragus equinus, Tragelaphus scriptus, a second species of Tragelaphus not yet determined, and Oreas derbianus. Buffaloes were said to be common on Deer Island, but they were not seen by me, though horns of two forms were obtained from natives. On the way back, a cutter was taken from Fatotenda to M'Carthy's Island, and after a few days spent at the Government House attending to m y collections, and m y living fishes and reptiles, I paid a final visit to Nianimaru. During this time, being the latter part of May, the rainy season began and the swampy places became filled with water. The Frogs began to spawn, and several series of stages in development of the different forms were preserved. Here I first obtained free swimming Protopterus with ripe ovaries: examples of 8 Frogs, 3 Chelonians, 5 Lacertilia, and 9 Ophidia, including a Typhlops, were also collected about this time. Returning to M'Carthy's Island, it was found that a number of Polypterus lapradii which had been kept in a pool connected with the river in the hope of getting them to spawn had been set free by the rising river. However, during the latter part of June and July a large number of Polypterus of both species were obtained, the females of which were crowded with ripe eggs. Artificial fertilization was tried with these, without success. Many were kept in confinement, and some, of which a pair are now exhibiled, were successfully brought alive to England. About the 10th of July, in the same swamp where these fishes were obtained, several nests of eggs were found. These eggs coincided in measurement exactly with the ovarian eggs of Polypterus. The young larvae possessed cement-organs on the front of the head so characteristic of Ganoid larva?; and other characters led me to assume that they were the young of Polypterus. None were reared beyond the larval state, and their identity could not well be established. However, having stayed on the Gambia three months longer than I had intended, and having a number of healthy Polypteri full of spawn, I decided to return home. Just a day or so before leaving M'Carthy's Island I obtained eggs of Protopterus. These were watched through the early stages of segmentation, but the young could not be reared. On July 25 I left M'Carthy's Island and returned to England. Several Polypteri and Protopteri, 12 young Crocodilus cata- |