Marine Protozoa from Woods Hole | Page 6

and one nucleus, which is situated a little above the body center. Fresh and salt water. Length without collar 9��; length of collar 3��.
[Illustration: Fig. 11.--M. fusiformis.]
Genus CODONOSIGA (Jas. Clark '67).
(B��tschli '78; Kent '81; Franc�� '97; Senn 1900.)
This genus, as modified by Franc��, is distinguished from the preceding by the possession of an unbranched stalk much longer than the body length. The body is naked and of various shapes, and the individuals are solitary or colonial upon a single stalk. Kent '81 enumerates no less than 10 species, which were cut down by B��tschli to 1. Franc�� admits 4--C. botrytis Jas. Clark; C. grossularia; C. pyriformis, and C. furcata, all S. Kent--but regards the second and third as merely form varieties of the first.
Codonosiga botrytis (Ehr. sp.) Jas. Clark '67. Fig. 12.
Franc�� gives the following synonyms: Epistylia botrytis Ehr.; E. digitalis Stein, Zoothamnium parasitica Stein; _Anthophysa solitaria Fresenius; Codonosiga pulcherrima Jas. Clark; Monosiga gracilis S. Kent; M. globulosa S. Kent; Codonosiga pyriformis_ Kent; C. grossularia Kent; (Franc��).
The individuals are small and provided with a long unbranched, or terminal, simply split stalk. The individuals are single or colonial. The Woods Hole form measured 22�� over all; the body was 5��, the collar 3��, and the stalk 14��. No colonies were seen, and only a few individuals upon red alg?.
[Illustration: Fig. 12.--Codonosiga botrytis.]
Genus BODO (Ehr.) Stein.
(Stein '59, B��tschli '83; Klebs '92; Senn 1900.)
The body is naked, usually amoeboid in its changes, and provided with two flagella, one of which is usually trailed along under and behind the animal. The anterior end is usually pointed, with the flagella arising from a minute depression; the posterior end is rounded. Specific characters very difficult to analyze. Fresh and salt water.
Bodo globosus Stein. Fig. 13.
The body during movement is globular or ovoid, without any anterior process. The trailing flagellum is invariably much longer than the vibratory one. The contractile vacuole lies in the anterior half of the body. Solid food particles are taken in near base of flagella.
Length of body 9 to 12��; diameter 8 to 11��. Common.
[Illustration: Fig. 13.--Bodo globosus.]
Bodo caudatus (Duj.) Stein. Fig. 14.
Synonyms: Amphimonas caudatus Duj.; Diptomastix caudata Kent.
The body is variable in shape, but usually flattened and pointed posteriorly. An anterior process is almost always present, and below this the flagella are inserted in a minute depression. The contractile vacuole is close to the base of the flagella. The flagella are about the same size, the anterior one usually somewhat longer. Common. Length 12 to 18��.
This species was seen by Peck '95 and described as a small flagellate.
[Illustration: Fig. 14.--Bodo caudatus.]
Genus OXYRRHIS Duj.
(Kent '81; B��tschli '86; Klebs '92; Senn 1900.)
Medium-sized forms, somewhat oval in shape, with a rounded posterior end. The anterior end is continued dorsally in a somewhat attenuate pointed process. At the base of this process is a large cavity or funnel, on the dorsal wall of which, or on a projection from this wall, are two equal-size flagella. When at rest, the flagella are directed backwards. The nucleus is central. In moving, the posterior end is invariably in advance. This genus is exceptional among Mastigophora in that division is transverse instead of longitudinal.
Oxyrrhis marina Duj. Fig. 15.
With the characters of the genus. Contractile vacuole not seen. Length 28 to 40��.
[Illustration: Fig. 15.--Oxyrrhis marina.]
Genus ASTASIA Ehr.
Flagellates with one flagellum, a spindle-form body and a high degree of plasticity, the contour constantly changing. A distinct, usually striped cuticle is invariably present. "Eye-spots" are absent. Fresh and salt water.
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 alg?. Length 60��; greatest diameter 30��.
[Illustration: Fig. 16.--Two aspects of Astasia contorta.]
Genus ANISONEMA B��tschli
Flagellates with two flagella, of which one is directed forwards and is concerned with the locomotion 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 octocostatus Stein '83; Sphenomonas Kent '81; Ploeotia vitrea Senn 1900.
With the characteristics of the genus. It differs from freshwater forms in having eight furrowed surfaces running somewhat spirally from the posterior to the oral end. Length 50��; width 23��.