SPH^EROPHORON. 



289 



black and tuberculated, while the endospore is pale but 

 thick; and the phenomena of germination prove the cor- 

 rectness of this view. In structure and development the 

 thecse and spores are similar to those of the genus Calicium. 

 When full of nearly ripe spores the theca is a very beauti- 

 ful object under the microscope, resembling a row of bluish- 

 black beads supported on a narrow, tapering pedicle. The 

 spermogones are similar in position and structure to those 

 of the following species, but are seldom seen. The geogra- 

 phical range of this and the following species is very wide, 

 occurring on rocks in the Arctic and Antarctic regions, and 

 almost throughout temperate and tropical countries, with 

 various exceptions or irregularities in local distribution. 



2. SpHjEROPHORON compressum (comprimo, to press to- 

 gether). Thallus greyish, frosted, having a somewhat rigid, 

 coral-like character, compressed, irregularly branched, fibril- 

 lose, — ultimate ramules as if articulated and swollen at the 

 apex. Apothecia obliquely placed, flattened or discoid, es- 

 pecially in old state, often with a reflexed margin. Spores 

 round. (E.B. 114.) 



Also somewhat common on the ground and on rocks in 

 alpine districts. Its spermogones occur towards the termi- 

 nations of the most delicate ramules ; under the lens they 



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