158 MAMMALIAN DESCENT. [Lect. VI. 



(Crossoptis fodiens) ; the smallest (Sorex pygmcBus) is 

 not only nearly the smallest of our native Mammalia, it 

 is almost the smallest of all the creatures that give suck 

 to their young ones. Its rivals in smallness are the 

 beautiful squirrel-like Harvest Mouse, who builds her 

 grassy nest among the multiplied (or tillered) stems of 

 a wheat-plant ; and the least of our native Bats, the 

 Pipistrelle. 



There are not only appreciable differences between 

 the skulls of the Land and Water Shrew, but in that of 

 the former I find varietal modifications. The shoulder- 

 girdle and breast-bone of these tyj)es is very instructive ; 

 this I have shown long ago ; there is a considerable 

 sternal, distal rudiment of the huge coracoid hone of 

 the Monotreme attached to the manubrium sterni 

 (or top of the breast-bone). 



Most of the elongation of the snout takes place after 

 birth ; nestlings of about the tenth, or twelfth, day have 

 a very proboscidean, or tapiroid a2:)pearance ; they are like 

 little Tapirs, with a long tail and short legs, or rather 

 they are like Cuvier's fossil Anoplotherinm. This middle 

 stage is very useful to the morphologist, for at that time 

 the various elements of the skull are easily traceable, the 

 bones being separated from each other by tracts of 

 cartilage, or membrane, as the case may be. These 

 small Insectivores agree with the Ant-eater and Pangolin 

 in having no cheek-bone (malar or jugal); in this they also 

 agree with the Insectivora of Madagascar (Centetidce) 



