PLATE IX. 



Fig. 1. — As remarked in the text, the contrast is too great in tliis photograph, 

 and the appearance of the Itrigliter regions is deceptive. In reality the darlc 

 regions in general represent the hydrogen tlocculi. though there may he a few 

 places near the sj)ot where bright tlocculi are present. 



Fig. 2. — This cut represents more nearly the appearance of the dark hydrogen 

 fiocculi on the negatives. As the slit did not coincide with the // line through- 

 out its length, the tlocculi are not shown to the west of the spot. A small bright 

 flocculus uuiy be seen at the extreme edge of the figure on the left adjoining 

 the small spot. 



154 



