299 



THE GENUS DISELMA. 



I. HISTORICAL. 



This genus was founded by Sir J. D. Hooker in his " Flora Tasmanica," 

 I> P- §53, t. q8, in 1859. Bentham and Hooker, however, Gen. PL III, 426, 1880, 

 place it under Fitzroya, a genus established by Sir Joseph D. Hooker in 1852 

 upon an evergreen tree — a native of Chili and Patagonia. As we have not been 

 able to procure specimens of the latter for comparison we retain Hooker's original 

 name for the same reason as Callitris is now the restricted name for Australian 

 trees in opposition to W iddingtonia and Tetraclinis, of South and- North Africa 

 respectively, and so preferring in this case the original classification of Sir J. D. 

 Hooker, until such time as the matter has been worked out on lines similar to 

 those laid down in this research. 



II. SYSTEMATIC. 



The onh" Australian species recorded is endemic in Tasmania. It is an 

 erect shrub with, as far as known, homomorphic, small, opposite, closely appressed 

 leaves in alternating ternary whorls. Flowers dioecious. j\Iale amentum terminal, 

 ovoid or oblong ; microsphorophylls opposite, in three or four pairs, filaments short, 

 the terminal leaf expansive, triangular and coriaceous, bearing two sporangia ; 

 pollen cells globose. Female amentum solitary, terminal, the leaves passing 

 abruptlv into the scales of the cones, the two uppermost and opposite pairs forming 

 the macrosporoph^-Us, with erect sporangia at the base of the inner ones. Fruit 

 cones small. Seeds, three-winged. 



Disclma Archeri, 



Hook, f., FI. Tasm., I, 353, t. 98. 



Habitat. 

 Tasmania — Western Coast Ranges, and Lake St. Clair. 



I. HISTORICAL. 



(^Vide supra.) 



XL SYSTEIMATIC. 



An erect, compact tree under 20 feet in height. Leaves exceedingly short, 

 \ line long, closeh* packed and imbricate, opposite, decussate or verticillate, obtuse^ 



