126 NOTICES OF NEW BOOKS. 



The remaining twenty-one species (beginning with Psaronius 

 Helmintholithus) all occur in a silicified state in the ' Rothe-todte- 

 liegende' or in alluvial soil, principally about New Paka and Mul- 

 hausen in Bohemia, and Chemnitz in Saxony. They have a very 

 great similarity to one another, and it may be doubted whether all 

 of the species distinguished by the present author will be admitted 

 by other botanists. There is however one remarkable, and appa- 

 rently important, anatomical peculiarity pointed out by him as cha- 

 racterizing certain species, namely Psaronius speciosus, P. alsophi' 

 hides, P. duhius, P. giganteusy P. asterolithus, P. parkericBformis 

 and P. macrorhizus. This is the presence of regular cavities or 

 lacunae in the cellular tissue, such as occur constantly in the tissue 

 of water-plants, whence M. Corda conjectures that the above-men- 

 tioned species were aquatic Ferns, like the recent Parkeria, which 

 is provided with similar lacunog. 



The largest of the Psaronii described in this work are P. HeU 

 mintholithus, P. intertextus and P, giganteuS) of which pieces as 

 much as twenty feet long have been found ; yet even these are said 

 to be much inferior in size to the American kinds. 



{5, DiplotegiacecB, — This family is established for the reception 

 of a single fossil stem, found, though but rarely, in the coal-sandstone 

 at Radnitz in Bohemia. Its outward appearance is somewhat like 

 that of a Lepidodendron ; the internal structure is very peculiar and 

 anomalous, but is thought by the author to come nearest to that of 

 the Marattiaceae. 



The work concludes with four tables ; — the first showing the 

 number of fossil plants in each formation of the earth, and the num- 

 ber of fossil Ferns in proportion to that of other plants ; the second, 

 an enumeration of living Ferns, distributed by tribes and according 

 to the zones of temperature in which they occur, each zone including 

 a range of ten degrees centigrade of average temperature ; also a 

 list of fossil Ferns by tribes, showing the proportion of the fossil to 

 the recent species known of each tribe. The third table enumerates 

 the arborescent Ferns known in a recent and in a fossil state, and 

 also the Marattiaceee known in each of these states, comparing them 

 with the total number of Ferns, recent and fossil. The fourth is a 

 list of the recent Marattiaceae, distributed according to zones of 10° 

 of temperature. 



M. Corda adopts Adolphe Brongniart's opinion that the tempera- 

 ture prevailing during the period of the coal-formation (including 

 the Rothe-todte-liegende) was very high, and this opinion he sup- 

 ports especially by the consideration of the great number of Marat- 

 tiaceae (Psaronii) found in that formation, since the rer.ent plants 

 of this tribe are almost confined to the tropical regions. 



Charles J. F. Bunbury. 



