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tiod. The pinnules of the original Hewardia are from 4 to 8 in. 
long, and are characterized by having a continuous involucre all 
around the edge, The involucre, however, is that of Adiantum, and 
when Sir Wm. Hooker came to publish his Species Filicum in 1858 
he stated that he could “not see thatit is agreeable to nature to sepa- 
rate a genus of ferns on account of the mere anastomosing of the 
veins of the pinnae.” By that time another species of Adiantum 
with reticulated veins had been discovered on the Pacific side of 
tropical America, and Hooker only noted the two by putting them 
inasection by themselves. Butten years later, when the Synopsis 
Filicum was issued, he made a sub-genus of Hewardia, founded on 
the venation, and included two other species having long but in- 
terrupted sori. One of these was the fern now collected by Rusby 
and Squires, which was originally named by Mr. Baker. All of 
these four Species belong to Guiana, although 4. ofvaceum has 
now been found in Venezuela, and A. dolosum occurs in Jumaica 
and on the continent from Guatemala to Brazil. The last named 
is the only one of the Hewardiae that can be regarded as at all com- 
mon, while A. o/ivaceum is a rare and very desirable species. 
_There.are-specimens-of three~arborescent : ferns in thiscollec- 
tion, viz,: Alsophila blechnoides Hooker; Hemitelia grandifola 
Spreng.; and Hemitelia Guianensis var. Parkeri Hook. In Hook- 
et’s Species Filicum he was inclined to regard H, Parkeri as dis-. 
tinct from H. Guianensis; but before publishing the Synopsis 
Filicum he had received a large suite of specimens from South 
America and became satisfied that the two supposed species were 
only slight varieties of one and the same thing. 7. Parkeri is 
distinguished by its more abundant hairs and by a larger number 
of sori which extend farther up the segments. Hemiiteha granai- 
Jolia is found in the West India islands as well as on the continent. 
The caudex of these species is so low that they can be called “ ar- 
borescent” only by courtesy and because they belong to a genus 
the Majority of whose species are truly arborescent. we 
: Another curious fern in the collection is Dryopteris menisciordes 
(Willd .) Unlike any other species of the Aspzdium section, its barren 
and fertile fronds differ in form, the fertile being contracted and 
made narrower by the excessive production of fruit. The entire 
under side of the pinnae is filled with the sori in regular lines, and 
