KOFOID AND SWEZY: UNARMORED DINOFLAGELLATA 237 



The girdle is siibmedian, its proximal and distal ends having a distance fi-om the apex of 

 (3.43 and O.K'I respectively of the total length of the body. It makes a slight anterior deflection 

 in the first 0.12 of its course, beyond which it takes a descending left spiral course around the 

 body, displaced postei-iorly at its distal end 0.25 transdiameter. The furrow is wide, about 0.07 

 transdiameter, and relatively shallow, witli smooth borders. The sulcus extends from the apex 

 to the antapex in a nearly straight line. The furrow is slightly narrower than the girdle and 

 lies in a wide trough (about 0.5 of the transdiameter in the middle of the body) which extends 

 down the ventral face of the organism, deepest in the girdle region and posteriorly, fading out 

 near the apex. Beyond the posterior pore the sides are detleeted laterally, forming a wide 

 excavation at the antapex. The anterior flagellar pore opens near the lower border of the girdle 

 at its proximal junction with the sulcus, the posterior pore a short distance anterior to tlie 

 antapex. 



The nucleus is spherical and is located just below the equatorial plane on the left side of the 

 body. Its chromatin contents could not be analyzed. Its axis is 0.35 transdiameter in length. 



The cytoplasm is finely granular and densely filled with large vacuoles, pinkish grey in color. 

 In the jjeriplieral zone are numerous blue-green oil droplets and dark, refractive granules, 

 evidences of holozoic nutrition. A small sacklike pusule opens into each flagellar pore. The 

 surface is striate with closely placed, equidistant, blue-green striae. The number of striae on 

 the hypocone exceeds the number ou the epicone by about 0.25. The color of the cytoplasm is 

 pearl grey with minute stippling of yellow ochre at the apices and near the girdle. 



Dimensions. — Length, 100/^ ; transdiameter, 68° ; transdiameter of nucleus. 



Occurrence. — A single individual was taken August 21, 1917, with a No. 

 25 net, 5 miles off La Jolla, California, in a haul from 83 meters to the surface. 



CojSEPArisons. — In the fineness and number of surface striae this species 

 closely resembles G. midtilincatum sp. nov. (fig. Y, 18), G. radiatum sp. nov. 

 (fig. Z, 9). and G. rifhniiit sp. nov. (fig. Y, 4) in the relatively wide displacement 

 of the girdle. In the latter I'espect these two species approach the Gyrodinium 

 type of gii-dle. It belongs in the subgenus TAneadinuim in a group of subbi- 

 conical to broadly ellipsoidal, rather finely striate species, including G. sitida, 

 G. diploconus, and G. radiatum, and has the maximum degree of displacement 

 of the girdle in this group. 



Gymnodinium musei Danysz 

 Text figure X, 3 



Giirnnodinium musei Danysz (1887), pp. 238, 239. 



G. musaci, Pouchet (1887), pp. 8!), 104, pi. 10, fig. 6. 



G. musei, Eutz, Jr. (1D09), pp. 262, 268. Lapsus. 



G. musei, Lemmermann (1910), p. 565, figs. 13-15, pp. 618, 619, 622. 



Diagnosis.— A minute species with broad body, its length 1.22 transdiam- 

 eters; girdle j)osterior, without disijlacement ; sulcus on hypocone only; two 

 minute red pigment spots. Length, 20a*. Fresh-water pools, Paris, France. 



Description. — The body is broadly ellipsoidal in ventral view witii broad apices, dorso- 

 ventrally compressed, its length 1.22 transdiameters at the widest part. The epieone greatly 

 exceeds the hypocone in size, its length being greater by 0.53. It is elongate hemispherical in 



