262 



R. M. Deeley — Suhmerged River-valleys. 



owing to the missing anterior premolar; p.m. 3 measures "4510. in 

 length and '25 in. in breadth, while the crown is "SS in. in height. 



The crown of the canine is supported by a strong sub-cylindrical 

 fang ; the inner surface of the crown is somewhat flattened and 

 bounded anteriorly and posteriorly by two sharp ridges passing from 

 the apex to the base. The external surface of the crown is strongly 

 convex and traversed by two short but fairly deep furrows near the 

 apex — the inner surface is without furrows. 



Fig. 2. Fragment of right upper maxilla of Lynx. Cales Dale Cave, Derbyshire. 

 Nat. size. p.m. 3 = third premolar ; c. = canine. Note entire absence 

 of second premolar ! 



The crown of p.m. 3 consists of a stout primary cone inclined 

 inwards, as in F. spelcea, but is without the usual secondary cusp on 

 the antero-internal aspect; the secondary and accessory cusps are 

 present behind, and divided from each other by clefts. A sharp ridge 

 traverses the tops of these cusps to the apex of the primary cone, 

 thence it continues as a blunt ridge down the antero-internal slope. 

 The cutting lobes are, therefore, all on the posterior slope of the tooth. 



The absence of p.m. 2 is remarkable and suggests reference to the 

 form known as F. brevirostris, but as this tooth is frequently entirely 

 wanting in small specimens of the lion, tiger, and F. spelcea,^ it may 

 not be of any great significance. 



YII. — Submerged Rivee-vallets. 

 By K. M. Deeley, F.G.S., Memb.Inst.C.E. 



BATHY METRIC surveys have revealed much that is very 

 interesting concerning the ocean floors, not only as regards 

 the deeper portions, but also as concerns the continental shelves. 

 Hull has constructed charts of the North Atlantic and shown that 

 many of the shallower areas are of such a form as to suggest that 

 they were originally portions of existing river-basins, and that the 

 submerged valleys may be traced along the sea bottoms to depths of 

 more than a thousand feet round the present continents. Similar 



1 Brit. Pleist. Mam. (Pal. Soc), i, p. 69, 1868. 



