December 7, 1900.] 



SCIENCE. 



873 



words 755 of the Montana and Yellow- 

 stone Park species are extending eastward. 

 This includes transcontinental and boreal 

 plants, as well as plain and prairie species. 

 Of these not more than half or not fully 20 

 per cent, of the whole number reach as far 

 east as the Alleghanies or the Great Lakes. 

 If the flora of Colorado should be com- 

 pared in a similar way with that of the 

 east, one would find that a much smaller 

 number of species was common to the two. 

 It is therefore safe to say that not 20 per 

 cent, of the plants of the Kockies are found 

 in the Alleghanian region and that these 

 consist almost exclusively of transconti- 

 nental and boreal plants. 



In comparing Montana with the Pacific 

 Coast, I found that 487 (mostly transcon- 

 tinental and boreal plants), plus 520 (mostly 

 Columbian and Cascade Mountain plants) 

 or 1,007 species or nearly 51 per cent, of the 

 plants of that State are also found west 

 thereof. These figures can not be taken 

 as a fair average, for in Colorado we find 

 fewer plants that are common to that State 

 and the Pacific Coast. I should judge that 

 even 20 per cent, would there be a high 

 number. I think, however, that it is safe 

 to say that between 30 and 40 per cent, of 

 the plants of the Rockies are also found in 

 some part of the Pacific Coast region. 



The families best represented in the 

 Eock Mountain flora are the following in 

 the order here given : Composite, Grami- 



NEiE, PapILIONACE^, CyPEEAOEjE, SceOPHU- 

 LARIACE.E, RoSACEiE, CeUCIPER^, RANTJNOU- 

 LACE^, CiCHOEIACEiE, PoLYGONAOEiE, OnA- 

 QEACE^, UmBELLIFER^. 



In Montana the composites (with Cicho- 

 EiACE^ and AMBEOSiACEiE excluded), con- 

 stituted about Ib^ per cent, of the species 

 of flowering plants, the grasses about 10 

 per cent., the pea family 6 per cent., the 

 sedges and rushes 5 per cent., etc. Of 

 CoMPOSiTiE over 45 per cent., of Geamine^ 

 over 41 per cent., and of PAPiLioNACEiE 



nearly 50 per cent., but of Cypeeace^ only 

 25 per cent, are endemic species. 



In Montana the following genera are rep- 

 resented by the largest number of species : 

 Carex, Seneeio, Erigeron,Potentilla, Pentstemon, 

 Astragalus, Poa, Aster, Ranunculus, Salix, Ar- 

 temisia, Polygonum, Castilleja and Eriogonum. 

 In the whole Rocky Mountain region these 

 genera will have nearly the same order, 

 except that Pentstemon and Polygonum have 

 to be moved slightly further down and 

 Eriogonum a little higher in the scale. 



P. A. Rydbbrg. 



A TERTIARY CORAL REEF NEAR BAIN- 

 BRIDOE, GEORGIA* 



This fossil coral reef is located near Rus- 

 sell or Blue Spring, about four miles below 

 Bainbridge, Decatur County, Georgia, along 

 the Flint River. My attention was first 

 called to the presence of reef corals in this 

 vicinity by finding two species, collected by 

 Professor Raphael Pumpelly, in the United 

 States National Museum. These species 

 were described by me in Monograph 

 XXXIX. of the United States Geological 

 Survey, under the names Stylophora minu- 

 tissima and Astrocoenia pumpellyi, both species 

 being compared with species from the An- 

 tiguan Oligocene. Subsequentlj', in Febru- 

 ary, 1900, Mr. Alfred H. Brooks, of the 

 United States Geological Survey, brought 

 me from the same locality a species of Orbi- 

 cella, which I identified with an Antiguan 

 species and specimens of Astrocoenia pum- 

 pellyi. Because specimens of Pecten {Pseuda- 

 7nusium) ocalensis Dall and Orbitoides were 

 brought with the corals, I referred the latter 

 to Dall's Ocala horizon of the Vicksburgian 

 Oligocene. It will be shown later that I 

 was mistaken as to the stratigraphic position 

 of the corals. 



Because of the interesting character of 

 the corals from Russell Spring, I requested 



* Published by permission of the Director of the 

 U. S. Geological Surrey. 



