50 TRUNK VERTEBRA. [chap. ' 



5 lumbar) in Tupaia, 19 (13 and 6) in Talpa and most 

 Soriddce, 19 (14 and 5) in Galeopithecus, 21 (15 and 6) in 

 Erinaceus, 22 (19 and 3) in Chrysochloris, to 24 (19 and 5) 

 in Centetes. 



There are also great differences in the development of the 

 processes of the vertebrae, which appear to accord with the 

 diversities in the habits and movements of the animal. The 

 transverse processes of the lumbar vertebrae are very short 

 in the comparatively slow moving, running, or burrowing 

 Hedgehogs (Erinaceus), Shrews (Sorex) and Moles (Talpa), 

 but they are very long, broad, and inclined downwards in the 

 jumping Macroscelides and Rhynchocyon, where the lumbar 

 muscles are greatly developed and the hinder extremities 

 disproportionately large. 



In the Mole, there are distinct, small, oval, flat ossicles on 

 the under-surfaces of the interspaces between the lumbar 

 vertebrae. Similar ossicles, but in a more rudimentary con- 

 dition, are occasionally found in the same situation in some 

 other Insectivora, as the Hedgehog, but not in any other 

 Mammals. 



. The usual number of thoracic and lumbar vertebrae in the 

 Chiroptera is 17, being either 12 and 5, or less commonly 

 ' 1 1 and 6. The transverse processes of the lumbar vertebrae 

 are almost obsolete, as are also the spinous processes through- 

 out the series. 



I Among the Rodentia, the most prevalent number is 19 ; 

 but it falls as low as 16 (13 thoracic and 3 lumbar) in Fiber 

 zibeticus, and rises as high as 23 (17 and 6) in Capromys, and 

 even as 25 (17 and 8) in Loncheres. 



The characters of the vertebrae vary much in the different 

 genera, as among the Insectivora. In the Hares (genus 

 Lepus) the anterior thoracic vertebrae have long slender 

 spinous processes; the lumbar vertebrae (see Fig. 3, p. 14) 



