3 1 4 CALAMARIEAE. 



during the formation of the Ostrau deposits, and thus arrives at last at a 

 phylogenetic arrangement of all the Calamariae. Calamites ramifer, Stur, 

 C. cistiformis, Stur, C. approximatiformis, Stur, and C. ostraviensis, Stur, 

 all figure in this list as transition forms. It need scarcely be observed on 

 what feet of clay the whole structure stands. But Stur goes much further 

 still in his conclusions. He places Sphenophyllum also with Calamariae on 



A 

 account of the trace-points on the nodes, and gives it the scheme B . For 



w 



this he relies chiefly on his examination of Sphenophyllum tenerrimum, 

 Ett. from the Culm ; but it may still be doubted whether this species 

 belongs to the genus, and the question will have to be considered later on. 

 He makes SpKenophyllum as well as Annularia and Asterophyllites to be 

 nothing more than heteromorphous branches of Calamitae, bearing two dif- 

 ferent kinds of fructifications, one of which therefore will contain macrospores, 

 the other microspores. He claims indeed to have found Sphenophyllae grow- 

 ing out of Asterophyllitae 1 , but he has not figured his specimens. It may 

 well be asked, whether they were not merely branches of broad-leaved and 

 narrow-leaved Sphenophyllum in connection with one another. The reader 

 should refer to the remarks on this point in the chapter of this work on 

 Sphenophylleae, and to Weiss' critical examination of Stur's views 2 . Lastly, 

 Stur r! , setting out from the results (?) thus obtained from fossil forms, 

 even attempts to arrive in the reverse way at conclusions respecting the 

 morphology of living Equisetae, which contain much that is surprising to 

 the botanist. Weiss' 4 summary account of these speculations should be 

 consulted. 



On the nodal line between the two rows of prominences, which have 

 now been described, the cast also shows the scars of the attachment of the 

 branches in varying number and arrangement. These are disk-shaped 

 surfaces, which are often somewhat depressed and patelliform, and at their 

 periphery they usually show radial striation 5 , due partly at least to the 

 mutual convergence in that quarter of the contiguous and laterally adjacent 

 ridges and furrows. In a figure given by Weiss 6 a small portion of the 

 stony substance has remained behind in the patelliform scar, and conceals 

 the peripheral striation ; and this is not an uncommon occurrence. In those 

 Calamitae which have only a few branch-traces in the nodes, we may often 

 observe on the nodal line outside and between these traces numerous 

 dot-like marks, to which a few adjacent ribs converge from above and 

 from below. It is natural to suppose that these marks are the traces 

 of undeveloped lateral branches. These traces are seen in a particularly 



1 Stur (10). 2 Weiss (8). 3 Stur (8). 4 Weiss (5), p. 13, note. * Weiss (5), 



t. 2, f. 3 ; t. 7, f. 2 ; t. 13, ff. 1-3 ; t. 21, f. 5; t. 25, f. i, and Stur (5), t. 20, f. 4. Weiss (5), 



t. 9, f. i. 



