122 MICROSCOPIC ANATOMY OF THE TEETH 



(24), and Professor Poulton long ago described blood-vessels 

 in the stellate reticulum of the rat (18). 



In fig. 71, from a preparation of the author's of Macropus 

 rufus, blood-vessels are seen crossing the external epithelium 

 and also lying within the stellate reticulum, an appearance 

 seen in many sections, and a photograph sent to him by 

 Mr. Law shows numerous blood-vessels in this layer. There 

 is little doubt that many preparations, said to show blood- 

 vessels in the stellate reticulum, really showed them, not 



**- v 



FIG. 70. The external epithelium in a human tooth germ showing 

 breaks of continuity and blood-vessels in contact with the stellate reticulum 

 (photographed from a preparation by Mr. W. James), e. External epithe- 

 lium ; 6. blood-vessels ; s. stellate reticulum. (x!50.)- 



in this layer, but in the connective tissue outside the enamel 

 organ, which, when the stellate reticulum has disappeared, 

 lies in contact with the stratum intermedium, and often 

 very strongly resembles it in appearance. There is, however, 

 no longer any doubt that vessels are found, at all events in 

 marsupials, within the enamel organ. 



Mr. Thornton Carter (5) has lately described blood-vessels 

 deeply within the stellate reticulum. 



It was long ago shown by Malassez and by Robin and 

 Magitot, that the external epithelium of the enamel organ 



