Bedford, Olfactory Neme in Swine. 



403 



This, however, is not found to be the case in those thick- 

 ened portions of the epitheHum of the same section where the 

 waviness of the mesodermal edge and the elevations occur. 

 By examination of Fig. 10, B it will be observed that some 

 nuclei have passed beyond the general line of nuclei and have 

 come to occupy a position much nearer the mesoderm. Fig. 

 10, C shows an outpitting of the epithelium in which the nuclei 

 lie upon the very border of the mesoderm, and a few lie only 

 partially within the epithelium. Fig. 10, rJ and (T are repre- 



Fig. 10. Three sections of the olfactory epithelium of a I2 mm. swine em- 

 bryo. A shows the nuclei in a row, located at a definite distance from the inner 

 margin ; B, nuclei that have moved slightly toward the mesodermal margin of 

 the epithelium ; C, nuclei in the act of migrating into the mesoderm from one of 

 the elevations of the olfactory epithelium. X 533^" ^^^'^ haematoxylin. 



sentations of different portions of the epithelium of the same 

 section. The general line of the nuclei lies about .00875 mm. 

 from the margin, while, as shown in Fig. 10, B, some of the 

 nuclei are within .0035 mm. of the mesodermal edge and in Fig. 

 10, C the nuclei lie directly at the mesodermal margin. 



At the time the elevations appear, many cells, showing 

 various stages of karyokinesis, are present. They are all lo- 



