VIEWS ON THE AFFINITY OF ACRADENIA. 



By Ferd. Mueller, Ph.D.,M.D., F.E.S., Corr. Member op 

 THE EoYAL Society of Tasmania. 



Among the few endemic genera of Tasmanian plants, Acia- 

 denia is one of the most remarkable. Its only representative, 

 Acradenia Frankliniae, Lady Franklin's tree, was discovered 

 by Dr. Jos. Milligan, on Franklin's Eiver, in 1842, and 

 phytographically defined by Mr. Eichard Kippist, in 1852. 

 (Transact, of the Linn. Soc. XXI., 200-207, t. 22). The precise 

 position of this plant among allied genera remained hitherto 

 unfixed, the perfect fruit being unknown. By the circum- 

 spect kindness of Mr. F. Abbott, the zealous Director of the 

 Botanic Gardens of Hobart Town, the writer has very recently 

 been favored with the opportunity of examining all parts of the 

 fruit, and thus to point out the affinities of the genus. In the 

 absence of any complete record of the carpological characters, 

 it may not be out of place to define these before the com- 

 parisons are instituted. 



Acradenia Kipp. 



Calyx persistent. Petals deciduous. Carpids free, 5 or 

 rarely 6, almost coriaceous, quadrate-ovate, about 4 lines long, 

 outside everywhere closely appressed-downy, at the outer 

 angle of the truncate vertex apiculate but not rostrate, along 

 the inner side and the vertex dehiscent, often only one or two 

 ripening. Endocarp bivalved, elastically secedent, short 

 saccate at the base. Placental membrane minute. Seeds 

 singly ripening in each carpid, about 2\ lines long, smooth, 

 cartaceous. Albumen, a thin imperfect stratum surrounding 

 the straight embryo. Cotyledons ovate, plane-convex, much 

 thicker than the albumen. Eadicle exceedingly short, 

 superior. 



From these notes it will be unexpectedly apparent that 

 Acradenia must be excluded from the Boroniaceous tribe of 

 Eutacese, with which it was temporarily arrayed, the main 

 characteristic of that group being a cylindrical embryo, with 

 a conspicuous radicle lodged in a large albumen. In trans- 

 ferring Acradenia to Xanthoxylese, of which tribe no other 

 forms occur in Tasmania, it is but right to point out, that 

 almost with equal justice it might be drawn to the tribe 



