318 LLOYD'S NATURAL HISTORY. 



which (Balczna affinis} resembled the Greenland Whale, while a 

 second (B. pnmigenia) was more nearly allied to the southern 

 Right Whale, and a third (B. balccnopsis) was cl iracterised by 

 its small dimensions. Hump-backs (Megaptera) were likewise 

 well represented, as were also the Finners (Bahcnopterd) ; while 

 an extinct genus (Cetothcrium) allied to the last, contains 

 several species from the Crag. It may be mentioned here that 

 all these Whales are represented by the shell -like tympanic 

 bones of the inner ear, which differ remarkably in form in the 

 various genera, and thus prove unerring guides both for generic 

 and specific determination. Another type of these bones, re- 

 markable for its egg-like form, serves to differentiate yet 

 another extinct genus (Herpetocetus) of Whale-bone Whales. 

 Turning to the Toothed Whales, a remarkable feature in the 

 Red Crag is the number of teeth indicating the occurrence of 

 large forms more or less closely allied to the Sperm-Whale, 

 but mostly distinguished by the presence of small caps of 

 enamel. There were likewise smaller forms, one of which has 

 long been known under the name of Physodon, although it was 

 only recently that the writer was able to determine from the 

 evidence of a Patagonian specimen that it differed from the 

 Sperm-Whale in having teeth in the upper as well as in the 

 lower jaw, and thus indicates a distinct and more primitive 

 Family connecting the Sperm-Whale with the Dolphins. That 

 a Bottle-nosed Whale nearly allied to the existing Hyperoodon 

 restrains inhabited British water during the Red Crag Period, is 

 proved by an ear bone in the Ipswich Museum ; and the num- 

 ber of Beaked Whales living at the same time must have been 

 extraordinarily great, from the profusion in which their dense 

 bony beaks occur in these deposits. Most of them belong to 

 the same genus (Mesoplodon) as that rare visitor to the English 

 shores, Sowerby's Whale ; although a few pertain to an extinct 

 genus (Choneziphiu-s) characterised by the presence of an un- 



