124 DOLEROPHYLLUM, CANNOPHYLLITES, EPHEDRITES, 



construction which is constantly observed in the stems described above, 

 and which is found in no existing Phanerogams except the Cycadeae.' 

 Judging from the figure I should say that the resemblance to the bundles 

 in Cycadeae is not too striking ; the bundle approximates on the transverse 

 section to the form of a five-rayed star with the initial strand lying in 

 the centre, and is surrounded by small-celled delicately walled tissue which 

 may be supposed to be bast. The three under rays of the woody strand 

 are connected together, and will of course have been regarded as the ' centri- 

 fugal xylem,' the upper rays which are separated by small intervals being 

 the 'centripetal xylem.' The epidermis of the under side is composed of 

 palisade-like cells with thin conically convex outer walls. On the upper 

 side the cells are shallow, but their outer wall is very much thickened and is 

 prolonged over each cell into a thorn-like process. We have already 

 observed a similar state of things in Cordaitae. In other respects the 

 vascular bundles are so imperfectly preserved, as I have been able 

 through Renault's kindness to satisfy myself by inspection of the original 

 preparations, that every definite statement about them must be taken with 

 caution. 



With these buds then Saporta 1 and Marion 2 associate certain round 

 entire leaves with a cordate base and auricles often overlapping one another, 

 which have the nervation of the leaves of the buds described above 

 (Nervatio Cyclopteridis) ; these leaves have been repeatedly found at 

 St. Etienne by Grand' Eury, and are attached, almost at a right angle as 

 it would appear, to small portions of branches which are in some cases pre- 

 served at their base or appear in the cross fracture. Together with other 

 remains they form the Doleropteridae of Grand' Eury 3 , and are figured in 

 a reduced but still recognisable form as Doleropteris pseudopeltata, Grand' 

 Eury 4 . Saporta's name is connected with Grand' Eufy's nomenclature. 

 These leaves do in fact agree very well in habit with the convolute leaves of 

 the buds before described ; still Saporta and Marion may be going too far, 

 unless they are in possession of proofs not yet given to the world, when they 

 maintain : ' It is certain that the leaves and consequently the branches 

 which they covered became detached at some time or other from large 

 conical buds,' &c. Noggerathia Cyclopteroides, Gopp. 5 , is the only form 

 cited from the older literature as belonging to the leaves of Dolerophyl- 

 lum, but Grand' Eury had already connected these with various species of 

 the fern-genera Cyclopteris and Nephropteris as defined by Brongniart 6 . 

 Like Brongniart and Schimper 7 , Grand' Eury inclines moreover to regard 

 all these objects as anomalous pinnae of the leaf-axes of Ferns, the so-called 

 Aphlebiae (see the chapter on Ferns), which are certainly not unlike them 



1 de Saporta (11). " Marion (2), p. 70. 3 Grand' Eury (1). 4 Grand' Eury (1) ) 



t. 16, f. i E. 5 Goppert (3), t. ai, f. 4. 6 Brongniart (2), p. 65. 7 Schimper (1). 



