144 MEMOIRS OF THE UNIVERSITY OF CALIFORNIA 



Amphidinium klebsi uom. sp. nov. 



Text figure U, 14 



Aviphidiiiium operculatum, Klebs (1884), pp. 723, 726, 732, 739, pi. 10, figs. 11, 12. 

 A. operculatum, Paulsen (1908), p. 96, fig. 128. 



Diagnosis. — A small species, with subeyliiicli'ieal body, its length 1.72 trans- 

 diameters ; girdle anterior ; ehromatophores ( ?) . Length, 46j^. Bay of Naples, 

 cai'ly spring months. 



Description. — The body is subeyliudrieal (dorsoventrally compressed?), rounded posteriorly, 

 subtruncate anteriorly \%-ith the middle portion drawn out in a slender tongue deflected to the 

 left. The length of the body is 1.72 transdiameters at the widest part. The tongue-shaped 

 portion at the anterior end is the epicone, which is separated from the rest of the body by the 

 wide girdle. The exact limits of the girdle and epicone are not shown in Klebs 's figures (1884). 

 Its length above the ba.se of the girdle is about 0.2 of the total length of the body, its width about 

 0.35 transdiameter. The hypocone is subcj^lindrical (flattened dorsoventrally?) with its sides 

 subparallel for the middle third of their extent, rounded above and below. The antapex is broad 

 and slightly rounded, while anteriorly the sides of the hypocone below the girdle swell forward 

 and outward, forming wide, high shoulders, the left one narrower than the right. 



The girdle is a wide circle embracing the narrow, neeklike portion at the anterior end of the 

 body. Its width is about 0.25 transdiameter. Its proximal border, as well as the sulcus, and the 

 connections of girdle and sulcus are not indicated in Klebs 's figures (1884). The longitudinal 

 flagellum arises a short distance below the probable point of union of girdle and sulcus. The 

 transverse flagellum arises in his figure on the right dorsal side of the body, a condition un- 

 paralleled in the dinoflagellates and one which is probably an error of drawing or interpretation. 



The nucleus is a large, spherical body occupying the posterior half of the hypocone. Its axis 

 is 0.43 transdiameter in length. The cytoplasm is fiUed with spherules of varying size and long, 

 tapering ehromatophores ( ?), which radiate forward and outward from the region of the nucleus 

 in the posterior part of the body. The color of the organism is not noted by Klebs. The surface 

 is apparently marked by a few longitudinal furrows or striae extending the length of the hypocone. 



DiMEXSioxs. — Length, 46^^; transdiameter, 28/^; axis of nucleus, 15a^. 



OccrBREXCE. — Figured by Klebs (1884) from the Bay of Xaples, where it 

 appeared in large numbers in the early spring months. 



Syxonymy. — This form was figured by Klebs (1884) as Amphidiiiiuni oper- 

 culatum Clap, and Laeh. It ditfers from that species in its narrowly constricted 

 girdle, touguelike epicone, ehromatophores radiating from the po.sterior end of 

 the body and the furrows on its surface. It differs as widely from Herchuan's 

 (1911) and Stein's (1883) forms of the same species. It is therefore proposed 

 to give it species rank with the name Amphidinium Mebsi nova. sp. nov. 



