296 



FLORA OF LOWER COAL MEASURES OF MISSOURI. 



Table showing distrihutmi in the Coal Measures of Great Britain of the plants of the 

 Lower Goal Measures of Missouri or of certain closely related si^ecies— Coutinued. 



Species. 



S. Lescnrianum T>. AV. (S. ohJonf/ifoUnm {Getm.) Ung.)- 



Lepidodendron BrUtsii Ls. (i. Worlheni Lx.) . ., 



L. lanceolatum Lx 



X. rimosiim Stb 



L. 8C«tote?ii.Lx. (i. opMurus Brongn.) 



Zepidostrohus 2'rinceps Lx. (Z. Geinitzii Schimp.) 



Lepidophylhim Jeimeiji D. W. (L. iriangulare Zeill.) ... 



L. Missourienae D. W. (X. majits Brongn. ) 



Slgillaria camptotwnia AVood 



S.iesseUata (Steinh.) Brongn 



S. ovata Sauv 



Stigviaria verrucosa (Mart.) S. A. Mill 



S. Evenii Lx 



Cordaiies communis Lx. (C. lorassifolius (Stb.) Ung.?). 

 Cordaianthus ovatus Lx. (C. Volhmanni (Ett.) Zeill.)... 



Blidbdocarpos multistriaius (Pre8l.)Lx 



Palceoxyris appendicitlala Lx. (P. carionaria Schimp.) . 



Millstone 

 grit 



Lower 

 Coal 



Measures. 



Identical species 

 Related species . . 



Middle 



Coal 



Measures. 



X? 



Transi- 

 tion 

 series. 



Upper 



Coal 



Measures. 



A glance at the accompanying table shows tliat the greater portion of 

 our species are found in the Upper Coal Measures and the Middle Coal 

 Measures of Great Britain. Whether in this table of distribution the 

 related species are excluded or taken into consideration, we find nearly 

 equal proportions of the floras occurring in either of these two groups. 

 The number of species found in the LoAver Coal Measures is but about 

 one-half that in either of the above-mentioned groups, and is, moreoA^er, 

 composed largely of plants of wide A^ertical range, found in one or all of 

 the above groups. It is important to note that the percentage of species in 

 the Millstone grit of Great Britain, as Avell as in the PottsAalle series of the 

 United States, is A'ery small, being practically insignificant. 



On the face of the numerical proportions it Avould seem that the Henry 

 County flora is so eA^enly diA'ided between the floras of both the Upper 

 and the Middle Coal Measures as to deserA'e consideration as intermediate 

 between them. The Sphenopteroid species, both identical and related, appear 



