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Show 1900.] ON THE BREEDING-HABITS OF WEST-AFRICAN FISHES. 835 sardous (Studiati). There are slight differences between the fossils of the two localities, but as they refer to secondary details which cannot be well demonstrated without figures, I must postpone their discussion. Mr. J. S. Budgett, F.Z.S., read a paper entitled " The Breeding-habits of some West-African Fishes, with an Account of the External Features in the Development of Protopterus annectens, and a Description of the Larva of Polypterus lapradii" in which a history was given of a collecting-trip made during the previous summer to the swarnps of tbe Gambia River in search of the eggs of Polypterus. The eggs of Polypterus were not discovered, though a very young specimen was found measuring only one inch and a quarter in length. In this small specimen the dermal bones were not developed, and tbe external gills were of very great size, the base of the shaft being situated immediately behind the spiracle. The dorsal Unlets formed a continuous dorsal fin. While the eggs of Polypterus were being searched for, the underground nests of Protopterus annectens were found in abundance, and a complete series of eggs and larvae were preserved. The male Protopterus was found to live iu the nest until the larvae were fit to leave it. The nests of this fish were made in but a few inches of water * frequently the water round the mouth of the nest was dried up, and then the parent was seen lashing the surface of the water in the entrance to the nest with the end of its tail out of w7ater. The larvae were provided with four pairs of plumose external gills and a ventral sucker as in Lepidosiren ; soon after hatchiug they attached themselves to the sides of the nest by the sucker and hung in a vertical position. The larvae hatched in eight days and left the nest as young Protopteri in twenty days. Thee xternal features iu their development were remarkably like those of the South-American Lung-fish (Lepidosiren), differing, however, from the latter in several details, which possibly could be traced to the presence in Lepidosiren of a larger amount of food-yolk. The colour change at night-time, which is found to be so marked in both members of the Dipneumona at a certain stage of their life-history, was discussed, and was shown in Protopterus to be associated with the nocturnal habits of the larva at this period. Nests wrere also found of Gymnarchus niloticus Cuv. These were made in about three feet of water and floated on the surface. The nests were two feet long and a foot wide, the wall of tbe nest standing several inches out of water except at one end, where it was two or three inches below the surface, and left an entrance to the nest. Inside the nest the depth of water was about six inches. The eggs measured 10 m m . in diameter; the larvae hatched in PROC ZOOL. Soc-1900, No. LV. 55 |