426 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Astasia contorta Duj. Fig. 16. 
Astasia inflata Duj. ’41. 
The body is colorless, transparent, and flexible. It is largest in the center, thence tapering at the 
two extremities. The surface of the cuticle is obliquely striated, giving to the animal a distinctly 
twisted appearance. The contractile vacuole is in the anterior neck-like portion of the body. The 
flagellum is inserted in a distinct oesophageal tube, into which the contractile vacuole empties. This 
tube is continued into a deeper pharyngeal apparatus of unknown function. 
Common in decaying algse. Length 60//; greatest diameter 30//. 
Genus ANISONEMA Biitschli. 
Flagellates with two flagella, of which one is directed forwards and is concerned with the loco- 
motion of the animal, while the other is directed backwards and drags after the animal when in motion. 
Body slightly compressed dorso-ventrally (fig. 17, section). An oral furrow is present on the ventral 
side and the two flagella originate in it (fig. 17, at left). The vacuole is on the left side. Food 
vacuoles are present in the posterior part. The nucleus is central. Movement creeping. 
Fresh and salt water. 
Anisonema vitrea (Duj.). Fig. 17. 
Synonyms: Tropidoscyphus odoeostatus Stein ’83: Sphenomonas Kent ’81: Plcentia vitrea Senn 1900. 
With the characteristics of the genus. It differs from fresh-water forms in having eight furrowed 
surfaces running somewhat spirally from the posterior to the oral end. Length 50//; width 23//. 
This attractive flagellate was quite common in decaying algse at Woods Hole; its shaking movement, 
