﻿Vol. 66. ,] FISH-BEMAINS FKOM NYASALAND. 251 



has flaked off, leaving only an impression behind, and a thickened 

 margin, on which is situated a group of small teeth, four indi- 

 viduals of- which, more highly magnified, are shown in fig. 7. 

 These teeth are somewhat closely placed, are small, rounded, 

 strongly striated vertically, with indications of an apical tubercle 

 which is not surrounded by an annular furrow or depression. 



Now, this is more or less the form of tooth described as occurring 

 in Colobodus, ascribed also to Serrolepis by Dames ; and if we assume 

 that the above-described scales belong to the same species of fish 

 as that which possessed this dentigerous bone, then Colobodus is 

 the genus. Such a determination is rendered more probable by the 

 resemblance, already more than once alluded to, of the scales of 

 species referred to the last-mentioned genus. I would, therefore, 

 propose that the name Acrolepis (?) africana should be replaced 

 by Colobodus africanus. 



Another dentigerous bone is shown in fig. 8, magnified three 

 diameters. It is a small linear piece of bone, set with one row of 

 minute cylindrical teeth, which appear to be quite smooth on the 

 surface. I give no opinion as to the genus to which this bone should 

 be referred. 



As regards the Palaeoniscidse, the present collection also yields 

 fragmentary evidence of their presence. In PI. XIX, fig. 9 is 

 represented the clavicle of a fish of this family, and in fig. 10 

 we see a caudal ridge-scale. It is manifestly impossible to name 

 either the genus or the species to which these two relics should 

 be referred. 



EXPLANATION OF PLATE XIX {pars). 



Pig. 1. Scale of Colobodus, africanus, Traq., type, magnified 2 diameters. 

 This, along with the other specimens brought home by Prof. 

 Drummond, is in the Eoyal Scottish Museum, Edinburgh. 



2. Scale of the same, magnified 4 diameters. 



3. Another scale of the same, magnified 4 diameters. 



4. A larger scale of the same, magnified 2^ diameters. 



5. Portion of a large scale of the same, magnified 3 diameters. 



6. Dentigerous bone, magnified 2 diameters (Colobodus africanus ?). 



7. Four teeth from the above-mentioned bone, highly magnified. 



8. Dentigerous bone, magnified 3 diameters. Genus unknown. 



9. Clavicle of Palaeoniscid, magnified 2 diameters. 



10. Caudal ridge-scale of Palaeoniscid, magnified 2 diameters. 



Discussion. 



Dr. J. W. Evans congratulated the Authors on the excellent 

 work w T hich they had carried out over a large area in the com- 

 paratively brief period of three years. He regretted that it had 

 not been possible to continue the survey. He thought that the 

 notes of Dr. Traquair on the fish-remains, as also the absence of 

 Gangamopteris, suggested that the Nyasa Karroo beds occupied 

 a high position in the Karroo System, and that the basement 

 boulders and conglomerates belonged to a higher horizon than the 

 Dwyka glacial beds. He believed that the Authors themselves 



