THE 



ALTERNATE-LEAVED SPLEENWORT. 



Aspleniwn germanicum. WEIS. 



The Alternate-leaved Spleenwort stands between the 

 Wall Rue and the Forked Spleenwort, sometimes, in- 

 deed, marked as a dubious species, but decided by 

 Moore to be perfectly distinct. It is one of the rarest 

 of our native Ferns, rare also in Northern and Central 

 Europe. In other parts of the world it is not known. 

 It is so rare here in Great Britain that Moore records 

 only one single variety. Its altitudinal range is from 

 300 to 600 feet above the sea. 



The Alternate Spleenwort grows in tufts, the fronds 

 from three to six inches high, sub-evergreen (the fronds 

 more or less persistent), narrow linear in general out- 

 line, pinnate, divided into distinct, alternate, wedge- 

 shaped pinnae, one or two of the lowest having gene- 

 rally a pair of very deeply-divided lobes, the upper 

 more and more slightly lobed, all having their upper 

 ends toothed or notched. The venation is very in- 

 distinct, on account both of the narrowness of the parts 

 of so small fronds and of their opacity. There is no 

 midvein, but one of the venules extends to each of the 

 teeth, each vein entering from the base becoming twice 

 or thrice branched as it reaches the broader parts .up- 

 wards, six or eight veins generally lying near together 



