468 MEMOIRS OF THE UNIVERSITY OF CALIFORNIA 



Dimensions. — Length, 75/^ ; transdiameter, 62/^ ; axes of nucleus, 35ft and 32/^. 



OccTJiiRENCE. — A single individual ^Yas taken August 21, 1917, with. a No. 

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

 surface and in a surface temperature of 22-5 C. 



Comparisons. — This species is a t}T^)ical member of the subgenus Pouche- 

 tielJa witli concentrated ocellus. It is close to P. voracis, but has a more highly 

 perfected ocellus, especially with reference to the lens. The epieone is higher, 

 tlie displacement less, and torsion greater than in P. voracis, which also lacks 

 the longitudinal striae characteristic of this species. The only other species in 

 Pouchetia with longitudinal striae are P. violescens and P. maxima, both ex- 

 tremely large species. P. voracis has, however, no close affinities with either of 

 these species. It is the most nearly spherical of all species of Pouchetia. 



Pouchetia subnigra sp. nov. 



Plate 6, figure 66 ; text figure 00, 6 



Diagnosis. — Body large, ovoidal, length 1.6 transdiameters; girdle a descend- 

 ing left spiral of 1.3 turns, displaced 0.6 transdiameter; sulcus with anterior 

 and posterior loops ; torsion 1 turn ; ocellus concentrated, posterior lens ; elong- 

 ated, laminate black melanosome with brown, central core. Length, 101m. 

 Pacific off La Jolla, California, July. 



Description. — This large species has an irregularly ovoidal body with its widest transdiam- 

 eter near the equatorial plane. The epieone is somewhat larger than the hypocone. Its apex 

 is broadly rounded, deeply grooved on the dorsal and left faces by the anterior loop of the sulcus. 

 Its length above the anterior flagellar pore is 0.2 and from its distal extremity is 0.8 of the total 

 length of the body. The hypocone is much narrower, approaching subconical, with rounded 

 antapex. This is slightly notched on the ventral face by the distal end of the sulcus. 



The girdle joins the sulcus 0.3 of the total length of the body from the apex. It sweeps 

 around the body in a uniform descending left spiral, making 1.3 turns and meeting the sulcus 

 distally at a point 0.17 of the total length of the body from the antapex, giving it a displacement 

 of 0.6 transdiameter. The anterior flagellar pore is located at the anterior junction of the girdle 

 and sulcus, the posterior pore near the posterior junction. The transverse flagellum traverses 

 0.7 of the total length of the furrow which is deeply impressed. 



The sulcus invades the epieone in a wide loop, making 0.6 turn and partly encircling the 

 apex. It forms a broad, rather deep trough, which indents the outline of the epieone. Its lips 

 are smooth and rounded. After its anterior junction with the girdle it narrows to about 0.5 

 of its width anteriorly and proceeds posteriorly as a rather shallow trough in a depression. It 

 makes 0.4 turn before joining the girdle distally, after which it invades the hypocone as a short 

 loop which notches the ventral face of the hypocone. 



The ocellus is large, 0.58 transdiameter in length, ventrally located, slightly posterior to the 

 equatorial plane at the left of the posterior end of the sulcus. Its axis is longitudinal and the 

 lens is directed anteriorly. The concentrated, laminated lens is pale bluish in color, oblong, 

 subovoidal, slightly asymmetrical in outline and has its base imbedded in the melanosome. The 

 melanosome is black with brown central core, large and irregularly rounded in outline, with 

 long, slender, granular, amoeboid strands extending out from it into the protoplasm. These 

 strands cross and form a kind of loose, open-meshed network close to the surface ventrall.v and 

 posteriorly. Other disconnected strands are found along the dorsal borders of the girdle and 

 of the sulcus beyond the anterior flagellar pore. 



