42 
normal direction and trend forwards (PL VIII, Pdgs 2 and 3). There is also 
an nneonformity, so to speak, between the scales immediately beneath the 
pectoral tin and the ordinary series of the flank. In a triangular area behind 
and beneath the clavicle (PL VII, Pig. 4), extending along the ventral aspect 
to a point below tlic middle of the longest pectoral ray, the scales trend 
downwards and forwards in slight curves of which the concave aspect is 
anterior ; and these, like the normal scries behind, arc terminated below by 
prominent ridge-scales. This ventral armature is well seen in several 
specimens, and evidently implies that the lower jiortion of the abdomen was, 
during life, broad, for each scale consists of a right and left half, apparently 
meeting at a very obtuse angle in the median line. The dorsal margin of 
the trunk is similarly provided with ridge-scales, but in this case much more 
acutely compressed from side to side. In badly preserved specimens this 
su})crior margin thus appears curiously serrated (PL VII, Pig. 7), and there 
is sometimes a deceptive scries of forwardly directed denticulations; but when 
the scales arc distinguishable, those of the ridge are seen to correspond in 
number with the normal series of the flank, none being crenulated, and each 
giving rise to only one backAvardly-turned point. 
licmarks . — So far as known, the South African species, C. Extoni, 
seems to be very closely related to the type-species thus described. It agrees 
well in the form and jn’oportions of the trunk, and it may bo that the 
dilferences in the proportions of the tins are due to imperfect preservation. 
In the dorsal and anal tins of C. Extoni^ however, a number of the anterior 
rays arc much more closely arranged in comparison with those that follow 
than is the case in (7. granulatus. 
ClEITIIROLEPIS [? ALTUS, 'UOC.'] 
Plate YIII, Pig. -i. 
Ohs . — As already mentioned, a single specimen in the collection is 
referable to a form of Cleithrolepis with a deeper trunk than that of the 
normal C. granulatus. This fossil is shown of the natural size in PL \ III, 
Pig. 4 ; and, apart from its shape, it is also interesting as exhibiting 
feeble impressions of the scales, which have been (carefully traced by Mr. 
Percy Ilighley, and somewhat emphasised in the drawing. 
The arched dorsal margin of the trunk in this unique specimen is 
much more angulated than usual, and the maximum depth (O' 098) exceeds 
the distance from the posterior margin of the operculum to the end of the 
