ON GENERA AND SPECIES. 57 
Oss.—The genera founded by Sir William Hooker, of 
which there are five, are marked with an asterisk, and the 
number of species named and described by him in the 
* Species Filicum " amounts to about 600. ` 
In a notice at the end of the fifth volume of the * Species 
Filicum,” he states, that “if his life and health be spared 
to him, he intends to accomplish a volume to be entitled 
* Synopsis Filicum,’ to contain brief characters of the sec- 
tions, genera, and species of Ferns, general habitats, and 
references to the ‘Species Filicum,’ omitting all really 
dubious species, and including the sub-orders Osmundacee, 
Marattiacee, and Ophioglossacee,” which it is hoped will 
form “a useful vade mecum for the travelling botanist, 
and the cultivator of Ferns, and for ready consultation in 
_ the herbarium.” 
.. Only one part, with the preface of this work, consisting ` 
of twenty-two pages, was printed at the time of the 
author’s death (which took place in August, 1865); the 
remaining manuscript was placed in the hands of Mr. 
J. Œ. Baker, who, shortly after Sir W. Hooker’s death, 
received the appointment of Assistant Curator in the Kew 
Herbarium, and who has carried out the author’s views, 
forming a volume of 482 pages, which was published in 
1868, accompanied by nine coloured plates illustrating the 
characters of the genera, of which there are seventy-five. 
In the arrangement of the tribes and genera this work 
does not differ materially from the ‘ Species Filicum 27 the 
number of species described of Gleicheniacem and Poly- 
Podiace» amounts to 2,122, being 279 less than the — 
“Species Filicum,” while 106 are enumerated under the - 
{sub-orders Osmundacee, Marattiacem, and Ophioglossacee, — 
thus making a total of 2,228 species, being chiefly founded. 
on Specimens in the Hookerian Herbarium, which, at tho ` " 
