CALAMARIEAE. 



321 



manner by means of repeated bifurcations. Of this fact there can be no 

 doubt in presence of Star's l many and excellent figures. The leaves in 

 older whorls stand out at a right angle from the axis ; at the upper ex- 

 tremities of the branches, which are preserved in great numbers, they 

 close over one another like leaves in a bud. This says little for the view 

 adopted by Heer 2 , on the strength of some evidently less perfectly pre- 

 served specimens, that the organs before 

 us are of the nature of roots. Moreover, 

 Stur 3 has figured several pieces of stem 

 curved at the base, and bearing on their 

 convex side small tufts of manifest roots, 

 which have small resemblance to the 

 leaves which we have been describing. 

 It is true that we find somewhat different 

 accounts of the foliage of Archaeocala- 

 mites in Brongniart 4 and Schimper 5 . 

 These accounts are based on a famous 

 specimen from the Culm of Burbach near 

 Thann in the Vosges and now in the 

 Museum at Strassburg, which consists of 

 a cast and a piece of the mould which 

 belongs to it. On the surface of the 

 transverse fracture of the, piece of stone 

 containing the mould is seen the half of 

 a leaf- whorl projecting at a .right angle. 

 This bit of whorl was taken by Brong- 

 niart for a close sheath having blunt 

 teeth. But Stur, with whom Schimper 

 in his later publications agrees, has 

 shown that each leaf in the whorl is 

 really free to the base, and that its 

 extremities which are of unequal length 

 are not the real apices. He has figured 6 a similar whorl from the 

 Moravian slates, which is spread out on the surface of the slate, like 

 the specimen from the Vosges, and also shows only the basal portions 

 of the leaves, all the rest having been lost by maceration and rending 

 before the plant was buried. The comparison of these leaves with those 

 of Calamitinae tells us of the great differences which there must have been 

 in the series of Calamariae. Sphenophyllum tenerrimum, Ett., which we 



FIG. 44. Vegetative branch of Archaeocalamites 

 radiatus with leaves repeatedly and dichoto.nously 

 branched. After Stur (6). 



1 Stur (6), t. 2, f. 8, and t. 5, f. i. 2 Heer (5), vol. ii. I, tt. 1-7. 3 Stur (6), t. i. 



Brongniart (1), t. 26, f. i. fl Schimper (4), t. i, f. c. 6 Stur (6), t. 2, f. 7. 



Y 



