PALEOZOTC! PL VNT.^ FRO^r CIKX.V.. 1 Ö 



III. Ta-p'u, Shêng-ching-Shêng.^' 

 CALAMITES si. 



PI. V. Fig.^. 3, 4, -,. 



Three fragments of au ec[uis9taceous plant which probably 

 belongs to a Calamités. The ribs are straight, almost flat, 1-1,') mm 

 broad and separated by shallow but distinct grooves. In one 

 specimen (fig. 4) the node is preserved, but in such a bad state 

 that it is not possible to see whether the ends of the ribs are 

 rounded or angular. 



Among the species of Calamités which can be compared with 

 ours is C. Suchowli Brgt (Hist. d. Végét. Foss. T, p. 124, pi. 

 XIV, fig. 6, XV, 1-6, XVI), to which indeed the Chinese 

 specimens show a great resemblance. 



What is highly interesting in these specimens is the presence 

 of circular flower-like disks sitting on their surfaces. In one of 

 them (fig. 5) there are two disks one above the other and close 

 together, and apparently a little above a node. In another one 

 (fig. 3) we see only a single disk. Such disks have already been 

 observed in species of Phyllotheca and also in Equiselum laterale 

 Phil, of the English Oolite (Seward's Fossil Plants I, p. 275, 

 fig. 63), and are generally considered to be nodal diaphragms 

 pressed out of the stem in process of fossil ization. Our disks 

 are not quite circular which may be due to distortion. Their 

 diameter varies between 6 and 8 mm. The central portion is 

 somewhat sunken and more or less smooth, and from it radiate 

 straight, spoke-like ribs which immediately or soon subdivide into 

 two and go over the slightly elevated rims to the periphery. 



1) ^-^.'^t^m 



