348 MEMOIKS OF THE UNIVERSITY OF CALIFORNIA 



To tlie single record made by Okamura for the Pacific we add in this paper 

 from the plankton off San Diego and La Jolla, California, the following species 

 previously described: G. cntenatum Okamura, C. lidix (Pouchet), C. puJchel- 

 lum Lebour, C. pirum (Sehlitt) ; and the following twenty-one new species: C. 

 at rom acid at urn, C. augustum, C. cavatum, C. cereum, C. citron, C. clarissimum, 

 C. conspirafum, C. convolutum, C. distortum, G. elongatnm, G. faurei, C. lebou- 

 rae. G. miniatum. G. radiatum, G. rosaceum, G. scliuetti, G. scintillans, G. tur- 

 Mneiim, G. viuction, G. virescens, and G. volution. 



The most widely distributed species is G. pirn m, recorded from the Mediter- 

 ranean, the Atlantic, and the Pacific. 



HisTOEiCAL Discussion 

 The genus Gocldodininm was established by Sclmtt (1896) for the forms 

 previously described as Gymnodininm without ocellus in which the girdle had 

 a length of 1.5 turns or more. His t}^e species was G. strangulatum (= Gym- 

 nodinium strangidatum Sehlitt (1895). He did not follow this up by sifting 

 out these species from Gymnodinium, and that was later done by Lenunermann 

 (1899) as follows: 



Gymnodinium archimedcs Pouchet (18S3) ^Cochlodinium archimedes (Pouehet) Lemm. 



Gymnodinium helix Pouchet (1887) ^Cochlodinium helix (Pouehet) Lemm. 



Gymnodinium con.strictum Sehlitt (1S95) ^ Cochlodinium consfn'cfum (Sehlitt) Lemm. 



Gymnodinium pirum Sehlitt (1895) ^ Cochl-odinium pirum (Sehlitt) Lemm. 



Gymnodinium geminatum Sehlitt (1895) = Cochlodinium geminatum (Sehlitt) Lemm. 



In 1908 Lohmann added to the list of species in Goclilodinium two species, 

 G. pellucidum and G. longum. The latter form has a girdle which seems to make 

 one turn only about the body, hence we regard it as a Gyrodinium, and have 

 tentatively placed it in that genus as G. longum. 



Okamura (1916) added one species to the genus, G. catenatum, and Lebour 

 in 1917 described G. pulchellum, liringing the total number of valid species in 

 the genus up to nine: G. archimedes (Pouchet) Lemm., G. catenatum Oka- 

 mura, G. constricfum (Schiitt) Lemm., G. geminatum (Schiitt) Lemm., G. helix 

 (Pouchet) Lemm., G. pellucidum Lohmann, G. pirum (Schiitt) Lemm., G. pul- 

 chellum Lebour, and G. strangulatum Schiitt. To these we add herewith twenty- 

 one new species from the plankton of the Pacific off La Jolla, California : G. 

 atromactdatum, G. augustum, G. cavatum, G. cereum, G. citron, G. clarissimum, 

 G. conspiratum, G. convolutum, G. distortum, G. elongatum, C. faurei, G. le- 

 hourae, G. miniatum, G. radiatum, G. rosaceum, C. scintillans, G. scliuetti, G. 

 turhineum, G. vinctum, G. virescens, and G. volutum. 



SUBGEXERA OF CoCHLODINnjlNI 



Subgenus 1. Cochlodinium subgen. nov. 

 Body not excavated sinistroventrally, girdle of 1.5 to 2, rarely 2.5, turns. 

 T^T^e species Gochlodinium strangidatum Schiitt. 



