LESQVEREUx] REVIEW OF CRETACEOUS FLORA. 321 



aside as rubbish. Anemidkim Scliimperi, Splienopteris fjrevillioides, etc., 

 of the Cretaceous Arctic iiora of Heer, are not more subject to satisfac- 

 tory determination than Lygodiiitn trickomanoides or Pterophylhim May- 

 denii. Moreover, this hist species, though imperfectly represented, indi- 

 cates a point of relation between the Dakota group flora and that of the 

 Cretaceous {Qiiadersandstein) of the Hartz Mountains in Germany. 

 Fragments of this kind are, therefore, doubly interesting by botanical 

 and geological affinities. 



Before entering farther into the discussion and comparison of generic 

 and specific types of the North American Cretaceous flora and of their 

 relation with vegetable forms described from Cretaceous formation of 

 other countries, I have to add a few remarks more on the third volume 

 of the Arctic flora of Heer, which was in ijublication at the same time 

 as that of the flora of the Dakota group, and of which I could give 

 ouly a short mention (p. 40), from a general synopsis formerly published 

 by the celebrated author. The Cretaceous flora of Greenland, which 

 con.'titutes the essential part of this third volume,* is in two parts. 

 Tijc first describes £>eventy-flve species from four different localities of 

 the north side of the peninsula of Noursoak, North Greenland, repre- 

 senting a lower stage of the Cretaceous. Of these, thirty-eight belong- 

 to rerns,t four to Lycopods and Equiseta, eight to Cicadese, sev- 

 enteen to Conifers, six to Monocotyledons, and one to Dicotyledons. 

 This flora is, therefore, composed of fifty-six per cent, of Acrogens, 

 Ferns, Lycopods, and Equiseta; twelve per cent, of Cycadete; twenty- 

 two per cent, of Conifers ; eight per cent, of Monocotyledons ; and one 

 per cent, of Dicotyledons. In the Ferns, the genera Asplenium, 

 Pecopteris, Gleichenia, are predominant, this last genus especially, which 

 is represented by thirteen species. In the Cicadese, the Zamites, five 

 sptcies ; in the Conifers, the Sequoia and Pinus, the first with five spe- 

 cies, the second with four. 



The second part of the Greenland Cretacejous flora describes remains 

 of xjlants, especially found in the southern part of the same peninsula. 

 Considered as Upper Cretaceous by the author, it has in sixty-two 

 species, thirteen Ferns, two Cycadese, ten Conifers, three Mono- 

 cotyledons, and thirty-four Dicotyledons. The relative proportion of 

 these plants is therefore far different, as here, fifty five per cent, are 

 Dicotyledons. In regard" to their generic distribution the predominance 

 is marked, in the Ferns by Pecopteris and Gleichenia^ in the Coniters by 

 Sequoia and Pinus^ and by Populus, Proteoides, Chondropliyllum, and 

 Magnolia, in the Dicotyledons. And in considering the general character 

 of the land vegetation of North Greenland, at the Cretaceous epoch, and 

 as far as it is known for the present by counting together the species of 

 both stations, we find it represented by a percentage of thirty-seven for 

 the Ferns, three for the Lycopodiacese and Equisetacese, eight lor the 

 Cycadese, nineteen for the Conifers, six and a half for the Monocotyle- 

 dons, and twenty five for the Dicotyled*ons, which therefore represent 

 only one-fourth of the whole. 



The first exposition of the Dakota group flora shows four species of 

 Ferns and six species of Conifers only. To this small number we have 



* A number of the Cretaceous plants of Cape Stairatschin, Spitzberg, are also described 

 in this work. They represent five Ferns, one Equisetum, nine Conifers, and one Mono- 

 cotyledon, or sixteen species. The predominance of Conifers is remarkable as well 

 as the absence of Cycadese and of Dicotyledons. Of these species, three Ferns and 

 three Conifers are identified with the lower Greenland flora, and five Conifers with the 

 upper, indicating an equal relation to both or an intermediate geological station. 



t By a misprint in the above exposition given in Cret. Flora, p. 40, the word Fucoida 

 is written for Ferns. 



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