KOFOID AND SWEZY: UNARMORED DINOFLAGELLATA 471 



OccuKEENCE. — This species was first taken 2 miles off La Jolla, California, 

 on July 3. 1906, with a No. 20 silk net in a haul from 155 meters to the surface. 

 Two individuals were taken July l(i, 1917, in a surface haul at the end of the 

 pier at the Biological Station at La Jolla in a surface temperature of 21? 5 C. 



Activities. — One individual moved slowly without rotation in anticlockwise 

 circles about twice the length of the l)ody in diameter. The movements of the 

 pigment, prior to cytolysis, in streams along the girdle and sulcus and in the 

 longitudinal lines coincident with or parallel to the longitudinal striae is sug- 

 gestive of an intimate relationship between locomotor organs and the metabolic 

 processes concerned in the formation and distribution of pigment. 



CoMPARisoxs. — This species is close to Ponclictin juno Schiitt in size, median 

 location, and horizontal axis of the ocellus as well as in its structure. The 

 differences lie in the striae of P. violescens, which are not recorded for P. juno, 

 \\hii-li has, moreover, peripheral linglike platysomes not present in P. violes- 

 cens. These are superficial characters, easily overlooked and possibly, in the 

 case of platysomes, evanescent. The structure of the girdle and sulcus, how- 

 ever, is different in the two species. Tlie anterior flagellar pore in P. juno is 

 0.3 of the total length from the anterior end, while in P. violescens it is 0.45 

 with a corresponding increase in the length and torsion of the apical loop of 

 the sidcus. 



P. violescens is a typical member of the sul:»genus Pouehcticlla and with 

 P. polypJienms and P. juno forms a group of large species with median ocellus. 

 A similar group of large species in the subgenus Poiichetia sensu strictu includes 

 P. maxima, P. vorncis, and P. fusus, in all of which the lens is lobed or sub- 

 divided. 



P. violescens is the only violet species thus far known among the Gynmo- 

 dinioidae. Pale glaucous l)luish colors are rather common and a darker blue 

 is known in Gymnodinimn coeriiletim. It is also the only species in Pouchefia 

 which is noticeably striate, the neai'est approach to striations appearing in 

 P. maxima and P. striata. 



Pouchetia voracis sp. nov. 

 Plate 8, figure 89 ; text figure PP, 2 



Diagnosis. — Large species with rotund body, its length 1.3 transdiameters ; 

 girdle with 1.25 turns aroimd body, displaced 0.4 total length ; sulcus with torsion 

 of 0.5 turn ; ocellus concentrated, median ; lens elongated, lobed ; pigment mass 

 with black, amoeboid melanosume with red central core; core, spinel red. 

 Length, 68m. Pacific off La Jolla, California, July, August. 



Description. — The body is large, rotund, broadly ovoidal in contour, with Ihe epicone and 

 hypocone sube(|ual. The epicone presents a large, hemispherical apex. Its length is 0.3 above 

 the anterior flagellar pore and at its distal extremity, 0.8 of the total length of the body. The 

 measurements of the hypocone are somewhat smaller, being anteriorly 0.7 and posteriorly 0.2 



