X] CALAMITIISfA. 369 



is in the Natural History Museum, Paris; it shows Astero- 

 phyllitean branches in organic connection with a Calamitean 

 stem, but it is not quite clear if the stem is a true Galamitina. 

 A large drawing of this interesting specimen is given by Stur^ 

 in his monograph on Calamites, also a smaller sketch by 

 Renault^ in his Cours de botardque fossile. Similar branches 

 of the Asterophyllites type attached to an undoubted Gala- 

 mitina are figured also by Lindley and Hutton. There is, in 

 short, good evidence that stems of this sub-genus bore branches 

 with Asterophyllitean shoots. 



The wood of stems of the Galamitina group of Calamites, 

 in some instances at least, was of the Arthropitys type ; this 

 has been shown to be the case in some French specimens from 

 the Commentry coal-field' and in others described by Stur^. 

 The pith-casts of Galamitina are characterised by comparatively 

 short interned es separated by deep nodal constrictions, as shown 

 in fig. 100. From Permian specimens from Neu Paka in 

 Bohemia, described by Stur", we learn that there were the usual 

 Calamite diaphragms bridging across the wide pith-cavity at 

 each node. Such a cast as that shown in fig. 100 is often re- 

 ferred to as Calamites approximatus Brongn. ; the length of the 

 internodes and the periodic occurrence of branch-scars in the 

 form of circular or oval depressions along a nodal line enable us 

 to recognise the Galamitina casts. Weiss" points out that in 

 pith-casts of this form the branch-scars occur on the nodal 

 constriction, and not immediately above the node as is the case 

 on the surface of a typical Galamitina. This distinction is 

 however of little or no value; the point of attachment of a 

 branch may be above the nodal line, while on the pith-cast 

 of the same stem the point of origin of the vascular bundles 

 of the branch is on the nodal constriction''. 



The specimen shown in fig. 100 illustrates the appearance of 

 a Galamitina cast. There is a verticil of branch-scarS on the 



1 Stur (87), PI. xTii. 2 Benault (82), PI. xvn. fig. 2. 



•" Eenault and Zeiller (88), Pt. ii. p. 434, Pis. lii. and liii. 

 * Stur (87), p. 37, fig. 17. Vide also Grand'Eury (90), p. 208. 

 « Stur, loc. cit. ^ Weiss (84), p. 61. 



' Vide Grand'Eury (77), PI. v. fig. 5. 



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