KOFOID AND SWEZY: UNARMORED DINOFLAGELLATA 217 



Gymnodinium grammaticum (Pouchet) emend. Kofoid and Swezy 



Text figure X, 22 



Gymnodinium puncfaium var. gram,m-aticum Pouchet (1887), p. 107, pi. 10, figs. 8-9. 

 G. punctatum var. grammiaticum, Lemraermann (1899), p. 359. 

 G. punctatum var. grammaticum, Schroder (1900), p. 13. 



DiAGxosis. — A minute si)ecies ^Yith rotund liody, its length and transdiam- 

 eter subequal ; girdle median, without displacement ; sulcus on hypoeone only ; 

 very long red pigment spot on ventral face of h\T)ocone in sulcus ; color yellow. 

 Length, 25/"-. Atlantic off Concarneau, France, September; Gulf of Naples, 

 July, August. 



Description. — The body is irregularly rotund, somewhat asymmetrical, rounded anteriorly, 

 notched posteriorly, its length and widest transdiameter subequal. The epicone and hypoeone 

 are subequal in length, but the hypoeone contracts less than the epicone. The epicone is hemi- 

 spherical in shape, flaring slightly posteriorly. Its length is about 0.5 of the total length of the 

 body. The hypoeone is rounded laterally with the antapex broadly notched by the distal end 

 of the sulcus. The right side is slightly longer than the left. 



The girdle is submedian in position. Its distance from the apex is about 0.5 of the total length 

 of the body. It forms a complete circle around the body, the ends meeting the sulcus without 

 displacement. The proximal lip is deeply undercut by the furrow. The sulcus is not well defined 

 in Pouchet 's figures (1887), but evidently extends at least from the girdle to the antapex. 



The interior of the body is filled with small spherules. The nucleus was not noted by 

 Pouchet. An elongated red pigment spot of exceptional size extends from the girdle to the 

 antapex in the suleal region of the ventral surface. The general color of the cytoplasm is yellow. 



Dimensions. — Length, 25-26/^; transdiameter, 23;^. 



Occurrence. — Figured by Pouchet (1887) from collections made in the 

 Atlantic near Concarneau, France, in September. The only other record of its 

 appearance is that of Schroder (1900) from the Gulf of Naples in July and 

 August. 



Comparisons.— A colored pigment spot of the t^^e found in this species is 

 rare among marine Gi/nnwdiuium, though rather common among fresh-vrater 

 species. It belongs in the subgenus Gijnuiodiniaut. 



