Cells elongated, attenuated, entire, aggregated in faggot-like bundles. The cells are fusiform or crescent-shaped, have no constriction at
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their centre, and are precisely like those of Closterium except in their aggregation, which is the only distinction between the two genera.
1. A. falcatus (Corda); bundles of numerous crescent-shaped very slender cells.
Dolgelley and Penzance, J. R. Sussex, Mr. Jenner. Ambleside, Mr. Sidebotham.
Italy, Meneghini. Germany, Ehrenberg, Kützing. Falaise, Brébisson.
Cells very minute and slender, crescent-shaped, fasciculated in irregular bundles composed of numerous individuals, which, as the convexity of each is turned inwards, diverge at each extremity of the bundle.
This plant is not unlike an early state of a Closterium, and as such I formerly considered it; but Corda, Kützing and Brébisson have pronounced it to belong to a distinct genus.
The bundles vary greatly in their compactness, as well as in the number of their cells.
Not having seen Corda's description and figure of Ankistrodesmus convolutus, I am unable to determine whether the present species differs from it.
Length of cell 1/549 of an inch; greatest breadth 1/7353.
Tab. XXXIV. fig. 3. a, b, c. aggregated cells; d. a single cell.
Closterium gregarium, Meneghini, Consp. Alg. Eugan. p. 17 (1837).
Xanthidium ? difforme, Ehr. Infus. p. 147. t. 10. f. 26 (1838) ?
Closterium falcatum, Meneghini, Synop. Desmid. in Linnaea 1840, p. 233.
Rhaphidium fasciculatum, Kützing, Phycologia Germanica, p. 144 (1845).
Ankistrodesmus gregarius, Brébisson, in lit. cum specimine (1846).
