PLATE 17 



Fig. 43. Ventjal view of theca of Gonyaulax polycdra Stein, showing 

 surface structure and plates. San Diego, California. June 23, 1904. 

 X 1000. 



Fig. 44. Ventral view of Gonyaulax turbynei Murray and Wliitting, 

 showing surface structure. San Diego, California, July 12, 1904. X 1000. 



Fig. 45. Ventral view of theca of Gonyaulax (Steiniella) alaskensis sp. 

 nov., showing plates and surface structure. Loring, Alaska, September 15, 

 1904. X 1000. 



Fig. 46. Dorsal view of same. X 1000. 



Fig. 47. Ventral view of theca of Gonyaulax polygramma Stein, show- 

 ing surface structure. San Diego, California, November 12, 1904. X 1000. 



Figures 43, 44, 46, 47 drawn by Mrs. Josephine Rigden Michener. 

 figure 45 by Miss Ethel Abeel. 



[286] 



