KOFOID AND SWEZY: UNARMORED DINOPLAGELLATA 435 



Concarneau on the west coast of France within the influence of the Gulf Stream. 

 The same influence accounts for the more northerly records of Miss Lehour 

 (1911h) of P. fusiis at Plymouth, England, and Pouchet's isolated record of 

 P. polifphemus in Dyrefjord, Iceland, and probably also for the records of 

 P. rosea in the North Sea and Cattegat off the coasts of Denmark by Ostenfeld 

 (1913). On the other hand, P. pnrva, recorded thus far both by Lohmann 

 (1908, 1911) in the Baltic at Kiel and by Miss Lebour at Ph-mouth, may be 

 more of a northern and neritic species. 



The only species recorded thus far from the Mediterranean are P. rosea 

 (Pouchet) by Pavillard (1905) at Cette and by Schroder (1900) from Naples. 

 The latter record may be for P. schuetti. The only species thus far reported 

 from the Pacific is P. pananiensis by Kofoid (1907a) from the Bay of Panama. 



To this single record for the Pacific we add in this paper from the plankton 

 off San Diego and La Jolla, California, the following species previously de- 

 scribed: P. rosea (Pouchet), P. juno Schiitt; and twelve new ones as follows: 

 P. alba, P. atra, P. maculafa, P. maxima. P. pouchcti, P. purpnresccus, P. pur- 

 purata, P. ruhescens, P. striata, P. snhiiigra, P. violesccns, and P. voracis. 



Historical Discussion 



This genus was established by Schiitt (1895), who figured P. rompacta 

 (called P. contorta in his explanation of plates), P. fasas, P. juno, and P. rosea 

 (Pouchet). His P. rosea is, however, not Pouchet's Gymuodiuium poti/pJiemns 

 var. roseitm (1887, pi. 10, fig. 1), but a distinct species, P. schuetti nom. sp. nov. 

 He also figured P. coeldea and P. cornuta, both of which lielong to Eri/tliropsis. 

 He later (1896) characterized the genus Pouclietia and established P. fusiis as 

 its type (monotypic). Pouchet in a series of papers (1884, 1885r/, 1885?>, 1886rt, 

 188G?>, 1887) called attention repeatedly to the ocellate forms of the dinoflagel- 

 lates. His figures are usually very incomplete and inadc({uate and his con- 

 ception of the species he dealt with Ijoth inconstant and confused. He regarded 

 them all as species of Gijmnodiniuyn. This lack of precision is due in part to 

 the difficulties in working with these delicate organisms, their small numbers, 

 and to the newness of the field. 



We regard his "Pcridiuinm- voisin de Gf/miiodiiiiniii spirale" (1885r/, p. 85, 

 pi. 2, fig. 1) as a Pouehetia, but indeterminal^le until some one finds the species 

 again. His G. poJi/phemus (1885&, p. 534, pi. 26, fig. 3) is a Pouehetia, but 

 different from his G. pol/jpliemus var. roseum (1887, ]>!. 10, fig. 1), which is 

 P. rosea (Pouchet), but not P. rosea (Pouchet) Schiitt (1895), which is P. 

 schuetti nom. sp. nov. His G. poli/pJioiius var. nigrum (1887, pi. 10, fig. 2), 

 which Lemmermann (1899) placed in Pouclietia, w(! transfer to the new genus 

 Protopsis. In 1907 Wright added P. oehrea to the genus. This we transfer to 

 Protopsis. In the same year Kofoid descril)ed P. panamensis, and in 1911 

 Lohmann added P. parva, which Ijy a slip of pen be(-ame (1911, p. 369) Pou- 

 ehetia paron. The same author earlier (1908, p. 152) introduced a nomen 



