MARINE PROTOZOA FROM WOODS HOLE. 
437 
Tiarina fusus (Cl. & Lach. ) emend R. S. Bergh. 
Synonyms: Coleps fusus Cl. & Lach. '58; Daday ’86; .Mobius ’88, Lanterborn ’94; Shevyakov '86. 
This form, which resembles C'olejxs rather closely, was placed as a separate genus by R. S. Bergh. 
The skeletal parts consist of five zones of needles composed of an organized substance and embedded 
in the cortical plasm, the last zone coming to a point at the posterior end. The needles have lateral 
processes, which give a latticed appearance to the casing. The cilia are long, with a specialized crown 
of still longer ones at the oral end; they arise outside of the skeletal elements and do not pass between 
them, as in Coleps. 
Key to marine genera of Trachelinidse. 
Diagnostic characters : Body bilateral, or asymmetrical by local prolongations; usually compressed or flattened later- 
ally, the left side more convex than the right. The essential feature is the position and character of the mouth. This is 
either a long slit extending from the anterior end well down the ventral surface, or the posterior part only of a ventral 
furrow remains open as a round or elongate month some distance from the anterior end. The entire mouth region of the 
body is usually drawn out into an elongate tapering proboscis which is generally curved dorsally at the extremity. An 
oesophagus is short or absent altogether; when present it is supported by a stiff buccal armature. Cilia are uniform about 
entire body or limited to the flat right side. Food is swallowed. 
1. a. Proboscis easily distinguished from the main body 2 
b. Proboscis not marked off from main body; body flat; both surfaces striated Genus * Loxophyllum, p. 437 
2. a. Mouth runs the entire length of proboscis; entire body uniformly ciliated Genus Amphileptus 
b. Mouth runs the entire length of proboscis; body flat; right side only is ciliated Genus * Lionotus, p. 438 
c. Proboscis much drawn out, flexible; mouth at its base Genus Dileptus 
Fig. 32. — Loxophyllum setigerum , var. armatum. a b, c, ventral, dorsal, and lateral aspects 
Genus LOXOPHYLLUM Duj. ’41. 
(Duj. ’41; Wrzesniowski ’69; Quennerstedt ’65; ’67, Cohn '66; Entz : 84; Gourret & Roeser '88; Butschli ’88; Shevyakov ’96. ) 
The body is flat and somewhat leaf-shape, flexible, and elastic. The anterior end is somewhat 
proboscis-like and flexible, but is not sharply demarcated as in Lionolus. The central portion of the 
body is developed into a more or less arched dorsal mass, which usually contains the nuclei and con- 
tractile vacuoles. As a result of this local thickening, the body is surrounded by a thin hyaline margin. 
This, however, may be absent on the right side in some species. The mouth reaches from the anterior 
