T 6o FILICES. 



Selenopteris there are two smaller bundles lying in its concavity. The 

 Tempskyae are different ; in one of them, Tempskya pulchra, Corda l , we 

 have several crescent-shaped bundles, one of which, the largest, often closes 

 into a ring. Goppert 2 again has figured fragments of Gyropteris and 

 Zygopteris from the Carboniferous Limestone of Glatzisch-Falkenberg in 

 Silesia, and with them, it is true, a form named Sphenopteris refracta, to 

 which we must return presently. Numerous figures of Zygopteris, Ana- 

 choropteris, and other Rhachiopteridae from the English Coal-measures, in 

 which the transverse section of the bundles differs from those already 

 described, are to be found in Williamson 3 . A number of petrifactions from 

 the Upper Devonian beds (Cypridina-shales) of Saalfeld, but almost all in 

 an extremely bad state of preservation, have been described by Unger 4 

 under many generic names. A large portion of these he has himself recog- 

 nised as Rhachiopteridae ; among them for example Clepsydropsis, which 

 in the form of the transverse section of the vascular bundles agrees pretty 

 closely with Williamson's Rhachiopteris duplex 5 . For some of the 

 remainder he forms the groups Haplocalameae and Stereocalameae, which 

 he would prefer to unite with Calamitae. After inspection of an original 

 preparation of Calamosyrinx devonica, preserved in the Museum of 

 Practical Geology in London, which belongs to the former of the two 

 groups, I should say that it is only the rhachis of a fern-leaf. What Unger 

 distinguishes in them as bundles of the pith may in fact be the vascular 

 bundles ; the outer peripheral woody body will correspond, as I imagine, 

 to the mechanical subepidermal ribs of sclerenchyma. The figures of 

 Kalymma 6 , Calamopteris 7 , and Calamosyrinx 8 should be compared. 



A very remarkable fossil is the old Medullosa elegans, Cotta, which 

 was afterwards named by Goppert 9 Stenzelia from specimens from the 

 Rothliegende of Chemnitz, and then Myeloxylon by Brongniart 10 from 

 material obtained at Autun. Both authors see more than one stock in 

 this form, and Goppert recognised it as one of his prototypes, which 

 uniting in themselves the anatomical peculiarities of different main groups 

 of the vegetable kingdom, in this case the Monocotyledons and the Ferns, 

 cannot be directly classed with any one of them. Williamson u has ex- 

 amined specimens from the English calcareous nodules ; the plant has also 

 been found in Bohemia with its structure preserved, for Corda's 12 Palmacites 

 leptoxylon and P. carbonigerus belong to it. Then on the strength of 

 searching examination of many specimens from Autun and Grand' Croix 

 Renault 13 declared that Myeloxylon is simply the stalk of a fern-leaf, and 



1 Corda (1), t. 58, ff. 1-5. * Goppert (12). 3 Williamson (1), vi, vn, x. Unger (5). 

 5 Williamson (1), vi. t. 55. Unger (5), t. i. 7 Unger (5), t. 2. 8 Unger (5), t. 3. 



9 Goppert (3). " Brongniart (2 . p. 109. ll Williamson (1), vn. 1J Corda (11, tt. 19, 20. 

 13 Renault (6). 



