194 
MARIE V. LEBOUR, 
and green remains of food are sometimes to be found inside the 
body, also small roundish masses of fat. 
The variety acutum Schiitt (Plate X XI, Fig. 66) is also found, 
which seems to be close to the typical form and more nearly 
the size of Bergh’s (1882) and Pouchet’s specimens. Length of 
this variety 0-14 mm. One specimen which occurred in August, 
1915, was coloured a beautiful carmine, the colour running along 
Fic. 19.—Spirodinium spirale (Bergh). *« 466. 
a typical form, 6 and c v. obtusum Schutt, d v. acutwm Schiitt. 
the lines of the strize in droplets. Other specimens are quite colour- 
less. 
The variety obtusum Schiitt is also common but of small size. 
Length 0-06 mm. usually. Characterised by its blunt apex. 
(50) Spirodinium concentricum n. sp. (Fig. 11). This species is 
characterised by the sculpture of concentric strive on the body, 
the longitudinal strize beimg arranged concentrically round a 
certain point at the side or on the dorsal surface. Body colourless. 
Grooves and shape of the body very much like the variety obtwsum 
of the preceding species. A large and a small form exist, the 
larger form being several times the size of the smaller. Both rare, 
only in the summer of 1915. 
