148 R. OWEN ON THE PURBECK 
10. On the Assoctation of Dwarr Crocopitus (Nannosuchus and 
Theriosuchus pusillus, e.g.) with the Dimrnurive Mamwats of 
the Purpeck Suares. By Professor Ricwarp Owen, C.B., 
F.R.S., F.G.8., &e. (Read November 6, 1878.) 
[Prats IX.] 
AGREEABLY with an intimation at the close of the Monograph 
(No. VIIL.) “On the Fossil Reptilia of the Wealden and Purbeck 
Formations,” which appeared in the volume of the Paleontogra- 
phical Society issued in 1878 (p. 15), I communicated to the 
Geological Society of London* a paper in which ideas suggested by 
the subjects of that Monograph on certain relations of Mesozoic and 
Neozoic Crocodilia to their prey were more fully detailed, and an 
instructive discussion was thereupon raised agreeably with the 
writer’s design. 
To his assumption that the mammalian prey of Neozoic Crocodiles 
were non-existent in Mesozoic times, an experienced paleontologist 
objected that such were in existence at those periods, and co- 
existed with the Teleosaurs and other amphiccelian Crocodiles t. 
It had not occurred to me that the mammalian prey of the 
Neozoice Crocodilest, which I had in view, and which were exem- 
plified in my mind and meaning by the Tiger, the Buffalo, and 
similarly large unguiculate and ungulate species, could be represented 
or suggested by the extinct mammals from the Purbeck and Stones- 
field strata, in the restoration of which, and the vindication of their 
claims to warm-blooded and mammiferous eminence, no small pro- 
portion of past paleontological work had been submitted by me in 
former days to the Geological Society §. 
Subsequent additions to our knowledge of Mesozoic mammals 
have not revealed any species approaching in size to the Ichneumons|!, 
which haunt the banks of the Nile, the Indus, or the Ganges. 
Such Viverrines are disdained by the large Crocodilia of these rivers ; 
at least the vermiform mammals are not known to fall a prey to them, 
or to call for the exertions, emerged or submerged, which the sub- 
duing of the struggles of a tiger or buffalo require. On the con- » 
trary, the attitude of the Crocodile to the small mammal is reversed ; 
the Ichneumon is the enemy and destroyer, in relation, at least, to 
* February 6, 1878; Quart. Journ. Geol. Soc. vol. xxxiy. p. 421. 
+ “Mr. Hulke observed that with respect to Prof. Owen’s idea that warm- 
blooded animals were not preyed on by the Mesosuchian Crocodiles, it could 
not be doubted that such did actually exist contemporaneously with them.”— 
Quart. Journ. Geol. Soc. 1878, vol. xxxiv. p. 428. 
¢ “Large species of warm-blooded mammals,” fom. cit. p. 423. ‘The ad- 
vent in Tertiary time of large mammalian quadrupeds browsing or prowling 
along the shores,” &c. p. 426. 
§ Trans. of the Geol. Soc. 4to, 2nd series, vol. vi. p. 47, pl. 5; Proc. of Geol. 
Soe 8vo, 1838, p. 17; Quart. Journ. Geol. Soc. vol. x. p. 426 (1854). 
|| Hlerpestes ichneumon, Cuy., 5 feet in length. 
