358 MEMOIRS OF THE UNIVERSITY OF CALIFORNIA 



Description. — The body is ellipsoidal, quite elongated, rounded anteriorly, truncate poster- 

 iorly, its length 2 transdiameters at the widest part at the middle. The left side is more 

 constricted by the furrows tlian the right. The epieone exceeds the hypocone in size, its length 

 being greater by about 0.1 of its own length. The epieone is elongate hemispherical, with a 

 length from the proximal and distal ends of the girdle of 0.27 and 0.76 respectively of the total 

 length of the body. The hypocone is less regular in outline than the epieone with a truncate 

 antapex slightly notched by the distal end of the sulcus. 



The girdle is a descending left spiral of 1.7 turns and a displacement of 0.94 transdiameter. 

 The proximal transdiameter of its course is nearly transverse, changing to a posterior direction 

 with an angle of 20° to 35° from the transverse plane, flattening again somewhat distally. The 

 furrow has a width of about 0.07 transdiameter and is deeply impressed with smooth borders. 



The sulcus invades the epieone in a short loop which fades out below the right side of the 

 apex. It turns posteriorly in a descending left spiral which makes one complete turn about the 

 body, terminating at the right side of the apex with a broad, shallow notch at the postmargin. 

 About 0.4 turn of its course takes place posterior to its distal junction with the girdle. The 

 furrow is shallow, but constricts the body rather deeply in the intercingular area. Its width is 

 about 0.5 that of the girdle, widening at the posterior junction to a slightly greater width than 

 that of the girdle, with a still greater deflection of its sides near the antapex. The anterior 

 flagellar pore is found at the anterior junction of the girdle and sulcus. 



The nucleus is a rather small, ellipsoidal body, located posterior to the midplane, near the 

 dorsal side of the body. Its major and minor axes are about 0.52 and 0.36 transdiameter 

 respectively. 



The cytoplasm is clear and finely granular and almost entirely free from spherules, vacuoles, 

 and food bodies. The color of the organism is yellow diffused through tlie cytoplasm. One 

 individual was enclosed in a spheroidal cyst with clear hyaline walls, very much larger than the 

 body. 



DiMK>:sioxs. — Length, 76^^; transdiameter, 38/^; axes of nucleus, 20^^ and 14/^; 

 diameter of cyst, 108f^. 



Occurrence. — This was ol^served July 9, 1904, in a haul made with a No. 

 12 net, 7 miles off San Diego, California, from 185 meters to the surface. 



CoMrARisoxs. — This species l^elongs in the C. strangulatum group of the 

 subgenus Cochlodinium. It is close to C. citron sp. nor. (fig. HH, 12) and has 

 less torsion, lacks radial rhabdosomes, and has a smaller apical region. It lies 

 in the line of differentiation leading to the subgenus Pohjdinium, with 3 to 4 

 turns of the girdle. 



Cochlodinium citron sp. nov. 



Plate 7, figure 79 ; text figure HH, 12 



Diagnosis. — A small species with elongated subelliiDSoidal body, its length 

 1.71 transdiameters; girdle a descending left spiral of 2.1 turns, displaced 0.88 

 transdiameter, sulcus without apical loop, torsion of 1.1 turns; color, amber 

 yellow. Length, 48/^. Pacific off La Jolla, California, July, August. 



Description. — The body is subellipsoidal, tending towards obovoidal, with broad apices, 

 slightly truncate posteriorly, nearly circular in cross-section, its length 1.71 transdiameters at 

 the widest part at the level of the proximal end of the girdle. The epieone exceeds the hypocone 

 in size. It is elongate hemispherical in shape with symmetrically rounded apex, and a length 

 at the proximal and distal ends of the girdle of 0.35 and 0.85 respectively of the total length of 



