FOSSIL FLORA. 777 



minosites, Init the fossil forms are not particularly satisfactory. The forms 

 referred to Acacia consist of well-defined pods and are somewhat con- 

 ventionally regarded as representing the modern Acacia. No leaves were 

 obtained that could with satisfaction be held as representing the foliage 

 of these pod-bearing shrubs or trees. The 2 species of Leguminosites are 

 supposed to represent leaflets of some leguminous plant, but beyond this 

 it is not possible to venture. 



The only remaining grouji of deciduous-leaved plants of any magni- 

 tude is the Sapindacete, with 5 species of Sapindus. One of these, Saj^iitchis 

 afflnis. is perhajis the most abundant form found among the Tertiary- 

 plants. The small characteristic leaflets are found in the greatest profusion. 

 The other species were less abundant. 



The other forms that re(|uire mention are: Ulmus, 4 species; Acer, 

 at least 2 species; Celastrus, 3 species, and Rhannuis, Paliurus, Zizyphus, 

 Cissus, Pterospermites, Tilia, and Rhus, with a single species each. 



The vascular crvptogams appear to have been a more prominent 

 feature of the flora during Tertiary times than at present. Of the 2 families 

 present, the Filices and Equisetacei*, the former is represented 1))- 10 and 

 the latter bv 4 species, while the living flora has liut (i ferns and 4 horse- 

 tails, all rare. 



The ferns were evidently abundant. They lielong to 6 genera, and are 

 represented in several cases by a large number of specimens. The largest 

 genus is Asplenium, with 4 species. The species described as AspUuhim 

 magnum is one of the largest and flnest forms tliat has been detected out- 

 side of the Carboniferous. Asplenium iddingsi is also a large, well-marked 

 species. The genus Dryopteris, the old Aspidium, is represented by 2 

 species, both of which are rather rare. They are, however, both fruiting, 

 a condition of micommon occurrence among fossil forms. There is also a 

 beautiful Woodwardia, quite closely allied to a species now living in the 

 eastern United States, and flne examples of the widely distributed climbing 

 fern {Li/fjod'mm kmilfusii). The only living North American species (L. 

 palmatuin) is found from Massachusetts and New York south to Kentucky 

 and Florida, and is generally rare throughout its range. The other ferns 

 are an (3smunda and a delicate form referred provisionally to the genus 



Devalha. 



The genus Equisetum, although represented by 4 more or less satisfac- 



