409 



moderately broad, and extends to the occipital ridge, where it joins the superoccipital and 

 mast old. There is no trace of interparietal. The frontal and sagittal sutures are obliterated, 

 and the frontals and parietals form a broad, smooth, continuous tract of bone, nearly flat 

 between the orbits, which the frontals define by large and long postorbital processes. The 

 sigmoid temporal ridges define the upper from the lateral surfaces of the parietal. The 

 malar is slender, but expands into a slight orbital angle. There is a distinct lacrymal, with 

 a small facial portion wedged between the frontal and maxillary. The antorbital foramina 

 are contracted, and defended externally by a short ridge directed forwards. The nasals in 

 this skull do not extend quite so far back as the premaxillaries. In the skeleton these bones 

 terminate on the same transverse line, and the nasals are more expanded and bent down 

 anteriorly. The coronoid process is well developed ; the angle and external ridge leading from 

 it are less marked than in most other Rodents. 



Mus. Brit. 



2266. The skull of the Java Squirrel (Sciurw bicolor). 



The teeth are removed from the right side of both upper and lower jaws, and separately 

 displayed. In this skull the borders of the external meatus are more developed, and are 

 notched inferiorly. The squamosal has been removed on each side, showing the vacuity 

 between the alisphenoid, parietal and petromastoid, which it covers. The basioccipital has a 

 median and two lateral ridges : against the latter the petrosals abut. The pterygoids do not 

 reach the petrosals. The bony palate extends backwards beyond the molar series. The 

 small antorbital fissure is not defended by the production of its outer boundary, but a tubercle 

 is developed from its lower part. 



Hunterian. 



2267. The skull of the Hudson's Bay Squirrel (Sciurus ffudsonius). 



The teeth are removed from the left side of both upper and lower jaws, and are separately 

 displayed. 



Hunterian. 



2268. The skeleton of the common Squirrel (Sciurus vitlgaris). 



The vertebral formula is: 7 cervical, 12 dorsal, 7 lumbar, 4 sacral, and 21 caudal. 

 Eight pairs of ribs directly join the sternum, which consists of seven bones. There is an 

 accessory ossicle between the scaphoid and trapezium. The pollex is very short and thick. 

 The hallux extends to the second joint of the index. The two fabellae are preserved behind 

 the condyles of the femur. The interspace between the ninth and tenth dorsals is that 

 towards which the spines of the other trunk-vertebrae converge. The anapophyses are sup- 

 pressed on the last two lumbar vertebrae. The characters of the humeri and femora, noticed 

 in No. 2264, are repeated in this skeleton. 



Mm. South. 



The following are parts of the same skeleton of a common Squirrel (Sciurus vulgaris) : 



Hunterian. 



