Lesquereux.] "IIO [Jan. 5, 



ceoiis, h:ilf conifei-s. Tliese plants are mostly known by their long linear, 

 ribbon -like leaves ; their stems have been very rarely fouml. Some large, 

 bushy species of Neuropteris have persisted. K. hirsuta and N. Loschi/ as- 

 cend from the Millstonr grit to the Permian. And above the Pit'sbiirgh 

 coal or even in connection with it are found the Callipteris : CalUpteri» 

 Moorii, and Callipteris conferta, this last species one considered in Europe 

 as Permian, and found by tlie Virginian geologists, Fontaine and White, in 

 the highest strata of the carboniferous. We have seen, however, that many 

 other so-called Permian types are remarked in the American coal measures 

 already from below the millstone grit ; and therefore, il is not as yet advis- 

 able to consider as Permian those upper strata which, beside this CiiUip- 

 teris, have a number of representations of truly carboniferous species. 



It remains only to state how far the work on tlie American coal flora 

 has progressed towards its completion. The plates, si.xt}' in number, are 

 all ready. The number miglit be still further increased b}' several species 

 which cannot be clearly represented by descriptions only ; l)ut wood cuts 

 may be used for the purpose, if it is advisable and possible to have any 

 iiitercallated into the text. The description of the species and the remarks 

 upon their diversified characters, as seen in the comparison of the speci- 

 mens, have been all written, and, therefore, the manuscript may be 

 definitely prepared in a short time. It is, however, not yet in its final 

 shape, as the records have to be left open for the admission of any valuable 

 (lata which the continued communications of materials wx&y bring to the 

 Flora. 



This synopsis is very incomplete, but it cannot be made comprehensible 

 without the tables of distribution, even if a large number of species were 

 enumerated. Moreover the limitation of the vegetable groups is not yet 

 definite enough. New and indeed ver}-^ desirable discoveries, especially 

 of plants of the Lower Carboniferous, the Vespertine of Pennsylvania, and 

 the Devonian Hamilton Coal Measures of the Juniata, may compel impor- 

 tant modifications. Therefore, the divisions as marked above, as well as 

 their names, should be considered only temporary. They are subject, of 

 course, to geological evidence which ought to govern them. The final 

 nomenclature of the groups of the "Coal Flora" must accord with that 

 of the Second Geological Survey of Pennsylvania. 



