1911] Kofoid: The Genus Gonuaulax. 209 



months later referred by Stein (1883, November) to G. spinifera 

 (Clap, et Lachm.) Diesing, a reference widely followed by sub- 

 sequent workers. The date of publication of Stein's (1883) 

 monograph is stated in a letter to me from the publisher to have 

 been the latter part of November. 



To these two forms I here add a third and still larger species 

 G. (liegensis, distinguished by its still larger size, widely dis- 

 placed but not much overhanging girdle, usually three antapical 

 spines, by its wide intercalary bands, and by the presence of 

 four apical plates. 



These three species form a series of increasing size compar- 

 able with that formed in the polygramma group by G. turhynei, 

 G. scrippsae, G. polygramma, G. kofoidi, and G. paeifiea, and 

 as in the case of that series, showing more or less intergradation. 



The possibility that they form merely a growth series is 

 excluded by their distribution, for in the case of the polygramma 

 series, G. Kofoidi and G. paeifiea are tropical and oceanic, and 

 the other two do not occur together with them in such numbers 

 as the growth relation demands. The possibility that they are 

 geographical (temperature) species or "races" is suggested by 

 the present incomplete data of their distribution, but it is by no 

 means conclusively determined. All three, spinifera, digitale, 

 diegensis, occur, perhaps together, in the San Diego region. Their 

 predominant centers of distribution must be determined to solve 

 this problem. In my opinion from data at present available they 

 are distinct species. 



The inclusion of G. triaeatdha in the spinifera group is an 

 arbitrary assignment, based primarily on the presence of several 

 antapical spines. Here also may be placed G. apiculata (Penard) 

 Entz. and its variety elerei (Ostenfeld). 



2. Gonyaulax spinifera (Claparede et Lachmann) Diesing 

 PI. 10, figs. 8-10; pi. 16, fig. 39, and text figs. A-D. 



Peridinium spiniferum Claparede et Lachmann (1858-1859), p. 405, 



pi. 20, figs. 4, 5. 

 Gonyaulax spinifera (Clap, et Lachm.) Diesing (1866), p. 96. 

 Peridinium sp. Levander (18941^), p. 50, pi. 2, fig. 21. 

 Peridinium vexans Murray and Whitting (1899), p. 327, pi. 29, figs. 



7a, b. See discussion of synonomy below. 



