. Dansk botanisk arkiv. Plants; Plants -- Denmark. Fig. 110. Galaxaura squalida Kjellm. Transverse section of the thaUus show- ing the periferic tissue with chroma- tophores and pyrenoids. (About 250:1), of numerous irregularly bent filaments felted together; these fila- ments have fairly thick walls and a breadth of about 16 /i while their length is often up to ten times the breadth. From this base several branches grow up and these are re- peatedly dichotomously ramified. The internodes are of very variable length from one to two cms. The branches are cylindrical, also in the dried condition
. Dansk botanisk arkiv. Plants; Plants -- Denmark. Fig. 110. Galaxaura squalida Kjellm. Transverse section of the thaUus show- ing the periferic tissue with chroma- tophores and pyrenoids. (About 250:1), of numerous irregularly bent filaments felted together; these fila- ments have fairly thick walls and a breadth of about 16 /i while their length is often up to ten times the breadth. From this base several branches grow up and these are re- peatedly dichotomously ramified. The internodes are of very variable length from one to two cms. The branches are cylindrical, also in the dried condition, with the exception of the quite young upper ends, not yet much incrusted which collapse being more or less flat when dry. In the spirit material the apices are nearly cup-shaped with the sunken growing point in the middle. The colour of the dried plant is a sordid yellow-green with a red-brown tinge espe- cially where the assimilating hairs are present. These do not occur evenly distributed over the whole surface; they are most numerously present upon the younger parts of the branches and often show here an annular arrangement but quite scattered ones also often occur especially upon older parts of the thallus. The surface of the plant is mostly rather clearly annulated. A transverse section shows that the medullary tissue is composed of rather thick- walled dichotomously branched filaments con- sisting of long cylindrical cells of which the diameter varies from 7 to 16 /i. The periferal tissue consists of short often dichotomously ramified cell-threads composed of 3—4 cells (Figs. 109, 110). Of these the innermost are the largest; they are mostly roundish but very large ones, irregularly shaped and lobed are often found (Figs. 109, 111). These lobed cells are also men- tioned and figured by Kjellman and occur in several other species. This cell layer is about 40/i thick, but the cells are very variable in size the large lobed cells being often much thicker. These cells are
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Keywords: ., bookcentury1900, bookcollectio, bookdecade1910, booksubjectplants
