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CHAPTER TWELVE
THE GENUS ENTRANSIA ELWYN HUGHES 1943
The genus Entransia was established to classify an alga having
simple filaments with cylindrical cells and one or two laminate
parietal chromatophores extending lengthwise of the cell, with
several irregular fingerlike processes extending outward and part
way around the cell. Each chromatophore has several scattered
pyrenoids. In young cells with a single chromatophore the nucleus
is laterally placed near the center of the chromatophore. In mature
cells the nucleus is in the bridge between the two chromatophores.
The orientation of the two chromatophores with the nucleus between,
the scattered pyrenoids, and the fingerlike processes extend-
ing outward and more or less enclosing the cell contents suggest
that the plant may belong to the Zygnemataceae. On the other
hand it may belong to the Ulotrichaceae near the genus Ulothrix.
Until the reproductive structures are found no definite disposition
of the genus can be made. Named for E. N. Transeau.
Description of Species
Entransia fimbriata Hughes 1943. Abstracts of Doctoral Disser-
tations, The Ohio State University, 40, pp. 153-59; also in
Amer. Jour. Bot., 35 (1948), p. 487.
Filaments with cylindrical vegetative cells 19-22.4 ft x 16-64 /a; i or
2 parietal chromatophores extending lengthwise of the cell, each with
several lateral processes partly embracing the cell contents. There is a
nucleus, in young cells located laterally and near the center of the
chromatophore; in mature cells with 2 chromatophores the nucleus is
in the bridge between them. (PL XX, Fig. 15.)
Canada, Nova Scotia, Queens County, Charleston, July, 1941. Collected
in a small artificial lake in the Port Medway River valley.
Here is an interesting note. In this same lake Hughes collected 3 new
species of Bulbochaete, i new Oedogonium, and a new Spirogyra. These
were the only new species of filamentous algae found on the peninsula
during two summer collecting trips, and in the examination of numerous
collections made by other residents of Nova Scotia. Many other collectors
have had similar experiences of finding one station that contained several
new or rare species not met with elsewhere in the same region during a
collecting period of several years.