380 MEMOIRS OF THE UNIVERSITY OF CALIFORNIA 



Cochlodinium schuetti sp. uov. 



Plate 1, figure 8 ; text figure HH, 2 

 &ymnodimum helix Sehiitt (1895), in part, pi. 24, fig. TTg. 



Diagnosis. — A meditim sized species with rotund ellipsoidal body, its length 

 1.47 transdiameters ; girdle a descending left spiral of 1.5 turns, displaced 0.52 

 transdianieter; sulcus with torsion of 0.5 turn; color, pale greenish yellow. 

 Length. 59/*. Pacific off La Jolla, California, July. 



Description. — The body is rotund ellipsoidal in shape with broad apices, nearly circular in 

 cross-section, its length 1.47 transdiameters at the widest part. The epicoue and hypoeone are 

 subequal in size, though the total lengtli of the former is slightly greater than the length of the 

 latter. The epicone is subhemispherical in shape with broad apex. It has a length from the 

 proximal and distal ends of the girdle of 0.38 and 0.75 respectively of the total length of the 

 body. The hypoeone is somewhat broader than the epicone, subtruncate posteriorly with the 

 autapex indented by the sulcal notch. 



The girdle is a descending left spiral of 1.5 turns and a displacement of 0.52 transdiameter. 

 The distance of its proximal and distal ends from the apex is about 0.38 and 0.75 re.spectively 

 of the total length of the body. The first 0.5 transdiameter of its course is deflected anteriorly 

 at an angle of about 30°, gradually changing to a transverse direction on the left side, turning 

 posteriorly on the dorsal face and again flattening to a transverse plane at its distal end. The 

 furrow has a width of about 0.05 transdiameter and is deeply impressed with rounded, over- 

 hanging borders. 



The sulcus may invade the epicone in a shallow loop which soon fades out or it may stop at 

 its proximal junction with the girdle. Its width is somewhat less than that of the girdle in the 

 intercingular area, expanding greatly posteriorly and forming a wide, rather shallow sulcal 

 notch at the antapex. It is deeply constricted in the intercingular area, resulting in a lobed 

 appearance of the ventral surface. The anterior and posterior flagellar pores are located at 

 the anterior and posterior junctions of the girdle and sulcus respectively. 



The nucleus is an ellipsoidal body filled with fine, moniliform chromatin strands following 

 its longer axis. It is located in the posterocentral part of the body near the dorsal surface. 

 Its major and minor axes are about 0.57 and 0.4 transdiameter respectively. 



Pusules may be present at either or both pores. In the individual figured the two pusules 

 were connected by a long slender canal, forming a tubular connection between the two pores. 

 The cytoplasm is very clear and transparent with numerous blue-green droplets scattered 

 through the peripheral zone. The anterior portion of the body was occupied by a large food 

 mass sea-foam yellow in color. Tlie color of the organism is a diffused pale greenish yellow. 

 A large, thin-walled, hyaline cyst enclosed each of the individuals observed. 



DiiMEXSiONS.— Length, 59-74j^; transdiameter, 40-50/^; axes of nucleus, 23/^ 

 and IG/'. 



OccrERExcE.— Two individuals were taken July 20, 1917, 6 miles off La 

 Jolla, California, with a No. 25 silk net, in a haul from 80 meters to the surface 

 and in a surface temperature of 21° C. 



Synonymy.— Sehiitt (1895) figured, as Gijmnodinium helix Pouchet, two 

 distinct forms. The first of these, shown in his figures 77i-.-,, plate 24, is evidently 

 Pouchet's species. His figure 77r., however, differs from the others in the shape 

 of the body, amount of torsion, and the posterior arrangement of girdle and 



