EXPLANATION OF PLATE XXI 



FOSSIL FUCOIDS FROM POGIBSHI ISLAND, NEAR KADIAK 

 VILLAGE, ALASKA 



Natural size 



FIGS, i and 2. Helminthopsis magna Heer. Page 144. 



1 . A small specimen of the Alaskan form of this species . The 



surface appears to be in a better state of preservation than 

 on the Swiss types of the species. 



2. A small portion of a slab containing a larger and wider speci- 



men ; figured to show corrugations of surface. 



