. Report of the Canadian Arctic Expedition 1913-18. Scientific expeditions. B^r h c. Siaurastrum Holmii nov. comb. [Cosmarium Holmii Wille). A, B, Cand D drawings of specimens found by the C. A. E. showing variations in shape from a two-sided form to a four-sided form. E reproduction of Wille's figures; all X 500; a, face view, 6, side view, c, end view. Staurastrutn Holmii (Wille) nov. comb. Cosmarium Holmii Wille. (Text fig. 5) This desmid was first described by Wille in the report of the Dijmphna- Expedition of 1882^. In his description he states: "This species occupies a rather separa
. Report of the Canadian Arctic Expedition 1913-18. Scientific expeditions. B^r h c. Siaurastrum Holmii nov. comb. [Cosmarium Holmii Wille). A, B, Cand D drawings of specimens found by the C. A. E. showing variations in shape from a two-sided form to a four-sided form. E reproduction of Wille's figures; all X 500; a, face view, 6, side view, c, end view. Staurastrutn Holmii (Wille) nov. comb. Cosmarium Holmii Wille. (Text fig. 5) This desmid was first described by Wille in the report of the Dijmphna- Expedition of 1882^. In his description he states: "This species occupies a rather separate position in the genus Cosmarium by its very broad sinus, so that it resembles certain species of Staurastrum. However, were it a Staurastrum, one would expect a tendency to three-cornered shape, but all the specimens I have examined proved to be regular when seen from above, with an equally large swollen place on each side of the semi-cells'.'' The specimens described by Wille have a form intermediate between (1) a form which has no swellings on the sides of the semi-cells and is elliptical in end view like all Cosmaria, and (2) a form in which the swellings have become so large that a typical four-sided Staurastrum is the result (Fig. 5, C). In consideration of this variation from two-sided to four-sided forms, and also in view of the fact that it has a broad sinus, I have come to the conclusion that it is really a Staurastrum and not a Cosmarium. The granulations were well marked in all specimens and differed but slightly in the different forms. >Wille, Alger fra Novaia Zemblia og KararHavet, samlede paa Dijmphna Expeditionen, 1882, Copenhagen, 1887. SI am indebted to Mr. F. Johansenfor this translation from the Danish Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Canadian Arctic Expedit
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectscienti, bookyear1919
