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XX. Some Observations on the Genus Andraa; with Descriptions of 

 four British Species. By William Jackson Hooker, Esq., F.L.S. 



Bead May 1, 1810. 



The genus upon which it is my intention here to offer a few 

 observations, was originally established by Ehrhart in the first 

 number of his Beiirage, and there received the name it has always 

 subsequently borne, in honour of his friend J. G. R. Andres, an 

 apothecary and able naturalist at Hanover. The only species 

 with which Ehrhart was acquainted was the J. alpina, a plant 

 that had long been known among botanists, but had always pre- 

 viously been joined to the Jungermamnce, between Avhich and the 

 Musci calyptrati it unquestionably forms the connecting link; 

 so that, though amid all the various changes and improvements 

 which have of late years taken place in the system of Mosses, 

 the genus Andrcea has had the peculiar good fortune of remain- 

 ing unaltered, yet a question has always arisen, how far it pro- 

 perly belonged to the order of Mosses, or Hepaticce ; its habit 

 being almost equally intermediate between both, and its cap- 

 sule seeming to partake more of the nature of the latter than of 

 the former. I shall briefly notice what has been done by those 

 botanists who have made any alteration in the character of the 

 genus, or in its place in the systematic order; and then proceed 

 to a description of the parts of fructification ; from which I trust, 

 VOL. X. 3d that 



