FOSSIL PLANTS. 471 



confined i<> only one. Tlii- table brings out more clearly than ever before 

 the facl thai the l);il<<>t;i <>)' the Denver Basin is quite intimately connected 

 wiili the Dakota of Kansas, Nebraska, etc., 1 »ut much more work will be 

 necessary before conclusive results can be obtained. 



It is interesting t" note- the presence or absence of certain types in 

 this Bora. Thus, it has no less than 1 conifers, 2 species of Ficus, '_' <>1 

 Aralia, 1 of Lauras, ."• of Magnolia, and species of thai anomalous genus, 

 Liriophyllum, Of those notable by their absence, the following genera 

 may be mentioned: Platanus, Populus, Liriodendron, Betula, Viburnum, 

 Protophyllum, etc. 



I.AKAMU. AMI JiKW \.H. 



At the time the earlier collections were made and when Professor 

 Lesquereux's work w;is 'lone, the differentiation between the Laramie and 

 Denver had nol been made, and inasmuch as both horizons are often plant- 

 bearing ;it the same localities, it became necessary to go over ;ill the m;it<-- 

 rial accessible and separate it according to this later knowledge. Tins 

 work was firsl done for the collection belonging to the United States 

 National Museum, ;m<l later for the material that is the property of < lolum- 

 bia College, New York, and Princeton College, New Jersey, with the result 

 of throwing importanl lighl on these two floras. Many corrections have 

 been made as regards locality and ;i number <>)' changes ;m<l eliminations 

 worked out. This has been much assisted l>\ the large recenl collections. 



It would be desirable to present in this connection ;i complete list of 

 the species thus far detected within the area under consideration, as has 

 been done for the Dakota plants, with ;i table showing their distribution 

 within the Denver Basin as well as outside, bu1 it has been thought inad- 

 visable al present; many of the species are new to science and have noi 

 vi-t been published, and to refer to them here, without description or i 11 1 is- 

 tration, would I"- to make them nomina nuda, and otherwise complicate the 

 synonymy. Consequently the present discussion is largely numerical, for 



Tin: collection ft Golden in the Museum of Comparative Zoology could not be completely 



utilized, as the catalogue bad unfortunately been lost, li baa since been fonnd, but too late to be 

 aged in tlii-* connection. \11 of the species mentioned by Lesquereux in his report on this collection 

 (Proc. Hub. Comp. Zool., Vol. XVI, No. 2) have been taken without revision, bul it i- more than 



probable thai changes will bi i essarj when it is thoroughly examined in the light of all recent 



information regarding this flora. 



