ORDER INSECTIVORA. 1457 



been regarded as allied to the Lemuroid Hyopsodus^ but Professor 



Osborn states that it is really very different. The dental formula 



21 x *z 



may be given approximately as I. -, C. - , Pm. % M. -. The two 



? 1 ? 3 



upper incisors have compressed crowns, somewhat like those of the 



two succeeding teeth ■ but the last two premolars and the true molars 



have broad and flat crowns, carrying a number of small cusps. 



Family Dimylidje. — This family is proposed by Dr Schlosser 

 for the genera Dimylus and Cordylodon ; two minute Insectivores 

 from the European Miocene which appear to be related to the 

 Erinaceidce. 



Family Soricid^:. — The Soricidce, or Shrews, are readily charac- 

 terised by their dentition, in which the first upper incisor is large 

 and furnished with a basal tubercle, while between it and the last 

 premolar there are a variable number of small incisors and premo- 

 lars, together with the equally minute canine. In the mandible the 

 number of teeth is always I. 1, C. 1, Pm. 1, M. 3 ; the incisor being 

 proclivous and much produced forwards, and the canine the smallest 

 tooth of the series. Existing species of Sorex, and perhaps of Crosso- 

 pus, occur in the Norfolk Forest-bed, while a species of the former 

 genus, regarded as extinct, has been recorded from the Pleistocene 

 breccias of Sardinia. Existing species of Sorex or Crocidura also 

 occur in the caverns of Madras. Numerous forms have been re- 

 corded from the Continental Tertiaries, ranging from the Miocene 

 to the Quercy Phosphorites, some of which are referred to Sorex, 

 while others, such as the Quercy species, have been regarded as 

 generically distinct, and named Amphisorex. Dr Schlosser thinks 

 that Orthaspidotherium and Pleuraspidotherium, mentioned on p. 

 1288, might be placed here. 



Family Talpidje. — The Talpidcs, or Moles and Desmans, are 

 closely allied to the Soricidoe, although easily distinguished by the 

 non-production of the first lower incisor ; they are usually of fos- 

 sorial, but in some cases are of natatorial habits. This family is 

 divided into the Myogalince and the Talpina ; in the former the 

 humerus and clavicle being moderately elongated. In this sub- 

 family the aquatic type genus Myogale, in which the dentition (fig. 



1341) is / -, C. , Pm. -, M. -, is represented in the Norfolk 



3 1 4 3 



Forest-bed by the existing Desman (M. moschata), of the rivers of 

 Russia ; the fossil form having been originally described under the 

 name of Palceospalax. Remains of this genus have also been ob- 

 tained from the Middle and Lower Miocene of France. Tetracus, 

 from the Lower Miocene of Ronzon, near Puy-en-Velay, is a small 

 Insectivore apparently presenting affinities both with Myogale and 

 Erinaceus ; and allied to this genus are two other imperfectly known 



