1516 



CORMOPHYTA, 



resembling those of Conifers, and showing great variation of struc- 

 ture in the different forms. The base of the stem generally termi- 

 nates in a blunt point (fig. 1384), and it may be attached to the 



rhizome, or several stems may spring 

 from a common stock, as in the 

 restoration figured. The roots are 

 cylindrical, and may be branching. 

 There has been great confusion in 

 regard to the determination of Cal- 

 amites owing to the difficulty of re- 

 ferring fruits, leaves, and roots to 

 their respective stems ; and also 

 owing to the fact that while in some 

 cases the entire stem is preserved, 

 in others only a cast of the pith- 

 cavity remains. According to Mr 

 Kidston the well - defined genera 

 based on stems are Catamites, rang- 

 ing from the Carboniferous to the 

 Permian ; Calamodadus and Astero- 

 caiamites, of the Devonian and Car- 

 boniferous ; and Arthropitys, of the 

 Permian. At least some of the 

 specimens to which the names An- 

 nularia and Asterophyllites (fig. 1382) 

 have been applied are branchlets of 

 Catamites. Fruits of Asterocalamites 

 have been described as Potho cites ; 

 while others known as Stachannularia 

 have been found attached to the 

 branchlets of Annularia. Other 

 fruits described as Volkmannia, Cal- 

 amostachys, and Macrostachya are 

 probably likewise referable in many 

 instances to Calamitea, although it 

 has been suggested that some may 

 belong to Spkenophyllum. Roots 

 known as Pinnularia have been 

 found attached to Catamites, but 

 some of the specimens to which this 

 name has been applied may belong 

 to other plants. There has been considerable discussion as to the 

 nature of the outer surface of the bark of Catamites, but it appears 

 from the most recent observations that in species with thin bark 

 this surface was fluted, while in those with thick bark it was smooth. 



Fig. 1383. — Part of stem of Cata?uites 

 cannceformis ; from the Carboniferous of 

 Europe. Reduced. 



