146 BOTANY OF CONGO. 



SO constant, that I am inclined to consult the relative 

 numbers of these two tribes, in determining whether the 

 greater part of any intratropicalTlora belongs to level tracts, 

 or to regions of such elevation as would materially affect 

 the proportions of the principal natural families : and in 

 applying this test to Barou Humboldt's collection, it is 

 found to partake somewhat of an extratropical character, 

 Poacese being rather more numerous than Panicese. While 

 in conformity to the usual equinoctial proportions, con- 

 siderably more than half the grasses in the Congo herbarium 

 consist of Panicese. 



Among the Panicese of the collection, there are two un- 

 published genera. The first is intermediate, in character, 

 to Andropogon and Saccharum, but with a habit very 

 different from both. The second, which is common to 

 461] other parts of the coast and to India, appears to connect 

 in some respects Saccharum with Panicum. 



The remarks I have to make on the Acotyledonous Plants 

 from Congo, relate entirely to 



PILICES, of which there are twenty-two species in the 

 collection. The far greater part of these are new, but all 

 of them are referable to well established genera, particularly 

 to Nephrodium, Asplenium, Pteris, and Polypodium. There 

 are also among them two new species of Adiantum, a genus 

 of which no species had been before observed on this line 

 of coast. Trichomanes and Hyinenopliyllum are wanting in 

 the collection, and these genera, which seem to require con- 

 stant shade and humidity, are very rare in equinoctial 

 Africa. Of Osmundacece, the herbarium contains only one 

 plant, which is a new species of Lygodium, and the first of 

 that genus that has been noticed from the continent of 

 Africa. 



Among the few species common to other countries, the 

 most remarkable is Gleichenia Hermann],^ which I have 

 compared and found to agree with specimens from the con- 



' Fnclr. Tlor. Nov. IIoll. 1, p. 161. Mcrtensia dicliotoma Willd. Sj). J?l. 5, 

 P 71. 



