ENDOGENS AND ACROGENS 



4'7 



Endogens and Acrogens 



Writers of descriptive works on gardening have so 

 often confined their survey of flora wealth to the kingdom 

 of Exogens, that custom has almost sanctioned the usage 

 of relegating the kingdoms above mentioned to separate 

 volumes. Of course it is very wrong; they were weary 

 of well doing errare humanum est. I myself, for 

 example, have treated the important and glorious family 

 of Orchids in two large volumes, and our Hardy Ferns 

 in a third, to which 1 must refer for details any who may 

 be interested in these subjects. Swiss mountains, both 

 Jura and Alps, possess rich collections stamped with the 

 picturesque charm which is so characteristic of both 

 orders. Yet to give a rounded completeness to the 

 present work 1 have included a few of the most typical 

 Swiss alpines from the various orders of the Endogens 

 and from the Ferns, promising that, if the welcome 

 accorded by the public encourages me to a full revision 

 at some future time, all omissions shall be made good to 

 the best of my powers. 



Orchis 



Everyone must have been struck by the sombre, yet 

 rich colouring of Nigritella angustifolia (Orchis nigra) 

 (PI. XC1I), called in French "Orchis vanille", and in 

 German "Schwarzstendel" or "Mannertreue", on account 

 of the strong vanilla scent of the pyramidal flowers, 



