KOFOID AND MICHENER: DINOFLAGELLATES. 271 



The ■polygramma group. 

 Characterized by prevalence of linear markings. 



GONYAULAX MINUTA, Sp. nOV. 



A minute subspheroidal species with barely suggested apical horn with 

 oblique apex. Length 1.1 transdiameters. Apex tilted to the left. Hypo- 

 theca hemispherical. Girdle descending, displaced 1 girdle width. Ventral 

 area not indenting epitheca, terminating posteriorly in broadly rounded 

 expansion. Ventral pore in apical 3'. Plate formula 3', a , 6", 6, 6'", l p , 

 1"". Apical 1' widened posteriorly; precingular 6" nearly square; post- 

 cingular 1' minute, triangular; posterior intercalary wide. Surface smooth 

 or faintly marked with linear striae. Girdle striate. No spines or lists. 



Length 20-25 n; transdiameter, 18-20 fi. 



Sta. 4720. 



GONYAULAX PAVILLARDI, sp. nOV. 



A small rotund or subangular species with predominantly linear markings. 

 Length 1.1 transdiameters. Body rotund, angled at apical-precingular 

 suture. Epitheca gradually contracted into short (1.5 girdle widths) squarely 

 truncate, apical horn. Hypotheca asymmetrically rounded, fuller on left 

 side. Ventral pore on apical 3'. Girdle descending, displaced 1 girdle width, 

 no overhang. Ventral area acutely and deeply indenting the epitheca, nearly 

 straight, its posterior plate subcircular, reaching postmargin, and often bear- 

 ing several antapical spinules. Plate formula, 3', ,J , 6", 6, 6'", l p , 1"". 

 Apical 1', narrow, widened posteriorly; precingular 6" quadrangular; post- 

 cingular 1'" very slender, less than 0.5 girdle width across; posterior inter- 

 calary wide, antapical 1"" mainly dorsal in exposure. Surface sparingly 

 reticulate with mainly longitudinal markings. Double ribs along sutures. 

 Pores in lines. 



Length, 48 /*,' transdiameter, 44 p. 



Sta. 4717. 



GONYAULAX RETICULATA, Sp. nOV. 



A small to medium sized species resembling G. polygramma Stein but 

 entirely without the characteristic linear markings. Body rounded, in smaller 

 forms scarcely angled at apical-precingular suture. Length 1.3 transdiame- 

 ters. Epitheca contracted to a stout apical horn with truncate apex. Hypo- 

 theca subhemispherical. Girdle descending, displaced 1.5 to 2 girdle widths, 

 no overhang. Ventral pore on apical 3'. Ventral area indents epitheca, 

 slightly curved, enlarged distally to left, reaching postmargin. Plate formula, 



