18 BAT-TRIBE. 
they differ chiefly in the presence of the small tubercle at 
the basal interspace of the exterior prisms; a difference 
which M. de Blainville regards as ground for doubting the 
legitimacy of their approximation to the Cheiropterous order 
at all.* Since, however, an anatomist so familiar by his 
recent researches with all the modifications of the teeth of 
the Mammalia had been unable to refer the fossil molars in 
question to any of the terrestrial or aquatic genera of 
Insectivora, but had given the figures of these molars a 
place in the plate illustrating the ancient Vespertiliones in 
his great work, the ‘“ Ostéographie,” I deduced from that 
fact, when preparing my Report on Fossil Mammalia for 
the British Association, additional confidence in my original 
determination. 
An extinct genus, new to science, of a Mole-like Insec- 
tivore, has lately come under my notice, in which the grind- 
ing teeth present the above described peculiar character 
of the minute tubercle at the basal interspace of the two 
exterior prismatic cusps. They are not, in other respects, 
identical, and additional fossils from the Kyson sand will 
be required to establish even the generic identity of the 
present small teeth from that formation, with the Palzo- 
spalax of the lacustrine beds at Ostend. 
* Ostéographie des Cheiroptéres, p. 93, pl. xv. fig. ix. 
