. Dansk botanisk arkiv. Plants; Plants -- Denmark. 98 Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 1 mm, with the hairs the diameter is more than 2 mm. The hairs are evenly distributed over the whole thallus giving it a felted appearance. The colour is rather variable, in some specimens red- brown in others greyish oHve-green with a more or less reddish tinge. As to the anatomical structure the medullary tissue consists of rather thick-walled filaments woven together. The filaments are of very variable size most often about 11—13/J. broad but some occur which reach more than the double thickness; the d
. Dansk botanisk arkiv. Plants; Plants -- Denmark. 98 Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 1 mm, with the hairs the diameter is more than 2 mm. The hairs are evenly distributed over the whole thallus giving it a felted appearance. The colour is rather variable, in some specimens red- brown in others greyish oHve-green with a more or less reddish tinge. As to the anatomical structure the medullary tissue consists of rather thick-walled filaments woven together. The filaments are of very variable size most often about 11—13/J. broad but some occur which reach more than the double thickness; the diameter of the whole tissue reaches a width of about 650 pt. Towards the periphery these filaments bare the polygonal sup- porting cells commonly found in this group (compare Fig. 103). These are mostly 4-gonal and about 40—50// broad. The assimilating filaments arising from these cells are of two different kinds, some short and others long. In the older parts of the thallus the long assimilating filaments especially occur while the shorter ones usually are very rare, in the young thallus the shorter assimilating filaments are quite as common as the longer ones. The short filaments consist of three, sometimes only of two cells (Fig. 103 6) and these cells decrease ra- pidly in size upwards. The lowest cells are large up to 10/j. or even longer and about 45// broad, the uppermost ones are only about 28 —30// broad. The basal cells in the long assimilating filaments are of about the same shape and size as those in the short filaments. Above the lowest largest one, a smaller oval cell follows and sometimes the following cell is yet somewhat swollen in the middle while the rest of the cells in the filament are cylindrical, mostly about. Fig. 103. Galaxaura lapidescens (Sol) Lamx. a, long assimilating filaments, b, short assimilating filament and basal part of a long one issued from the same sup- porting cell. (About 150:1).. Please note that these images are extracted from sc
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Keywords: ., bookcentury1900, bookcollectio, bookdecade1910, booksubjectplants
