KOFOID AND SWEZY: UNARMORED DINOFLAGELLATA 393 



Torodinium teredo (Pouchet) 



Text figure 11, 4 



Gymnodinium teredo Pouchet (ISSoa), pp. 67, 82, 88, pi. 4, fig. 29. 



G. teredo, Schiitt (1895), in part, pp. 5, 6, 65, 71, 109, 115, 117, pi. 23, figs. 743_,„. Figs. 



74]_2 are Torodinium robiisUtm nom. sp. nov. 

 G. teredo, Lemmermaun (1899), p. 358. 

 G. teredo, Schroder (1900), p. 13. 

 G. teredo, Karsten (1907). p. 307. 



G. teredo, Paulsen (1908), in part. pp. 97-98, fig. 132. 

 G. teredo, Lebour (19176), in part (?), PP- 188, 197. 



Diagnosis. — Mediimi sized species, body elongate, subfusiform, length 4.3-5 

 transdiameters ; epicone forms 0.88-0.91 total length; girdle forms proximally 

 a descending left spiral, without overlap, displaced less than 1.5 furrow's width; 

 sulcus with torsion of 0.5 turn adjacent to the girdle, no loop at apex. Length, 

 100-113^. Atlantic, Pacific, and Indian oceans, Plymouth Sound, Mediter- 

 ranean. 



Description. — The body is elongate asymmetrically subfusiform, left side (of sulcus) more 

 convex, widest near the middle, length 4.3-5 transdiameters measured at the widest part : epicone 

 very greatly exceeds the hypocone, forming 0.88-0.91 total length of the body ; the hj'pocoue is 

 subconical with an angle of 50°, with its axis ventral to the main axis and the dorsal slope nearly 

 twice the length of the ventral, with pointed antapex. In combination with the girdle it forms 

 a single turn of a descending left spiral, with a total displacement dorsally of about 1.5 widths 

 of the furrow. The proximal 0.5 turn on the left side descends 20° from the horizontal to the 

 middorsal line, but ascends again in the distal part with the result that the ventral face of the 

 hypocone is longer than the dorsal (fig. II, 4). There is no overlap. The furrow has an over- 

 hanging anterior lip and is deeply impressed. Its width is about 0.12 transdiameter at the 

 widest part of the body. 



The sulcus originates anteriorly within a short distance of the apex, runs longitudinally 

 posteriorly to within 1 transdiameter of the antapex, turns in a descending left spiral for 0.5 

 turn at about 45° to its junction with the girdle on the opposite side. It is not distinguishable 

 beyond this point. It has no reversed loop in the anterior end of the bod.y. The flagellar pore 

 lies near the junction of girdle and sulcus. 



The nucleus is elongated cylindrical with rounded ends. Its major and minor axes are 

 respectively 3 and 0.45 transdiameters in length. It is traversed diagonally by 8-10 vaguely 

 outlined spiral chromatin strands and its boundaries are indistinct. A longitudinal pusule, 

 opening posteriorly at the flagellar pore, runs anteriorly nearly to the apex. It may be broken 

 up into a line of separated vacuoles (Schiitt, 1895). Refractive fatty spherules of varying sizes 

 are clustered near the apex and along the right side and an axial plastid containing what Schiitt 

 (1895) has called fi-oW may be located in the anterior half of the epicone. Ochraceous chromato- 

 phores or rhabdosomes arranged in four longitudinal rows of rods from 0.5 to 1 transdiameter 

 in length and about 0.1 in diameter are found on the left side for the middle 0.7 of the total 

 length of the body. Several additional stouter chromatophores or rhabdosomes as radii are 

 found above the four rows near the apex. They are clustered about a central oil spherule. 



The plasma is almost colorless and shows no peripheral striae. 



Di.MKNSiONS. — Length, 100-11 3m; transdiameter at widest part of the body, 

 23-26^ ; axes of nucleus, 75/* and lO/i. 



