X] CALAMITIXA. 37 1 



strobili, either Palaeostachya or Calamostachys, in close associa- 

 tion with Calamitina stems, and Renault and Zeiller' give 

 illustrations of the association of Calamitina stems with large 

 strobili of the Macrostachya form. 



Before Weiss proposed the term Calamitina, various 

 authors had figured this form of Calamite under a distinct 

 generic name {e.g. Hippurites of Lindley and Hutton^ 

 Cyclocladia^, Hacrostachya^, &c.). Stems of this type have also 

 been described by more recent writers under different names, 

 and considerable confusion has been caused by the use of 

 numerous generic designations for forms of Calamitina. Some 

 small fragments of Calamitina stems were described by Salter" 

 in 1863 as portions of a new species of the Crustacean 

 Eurypterus {E. mammatus). In 1869 Grand'Eury proposed 

 the generic name Calamophyllites^ for stems bearing verticils 

 of Asterophyllites shoots ; his description of such stems agrees 

 with Weiss' Calamitina, but as Grand'Eury's name is used in 

 a narrower sense as implying a connection with Asterophyllites, 

 it is more convenient to adopt Weiss' term in spite of the 

 priority of CaZamophyllites. In the Fossil flora of Commentry 

 we find some flattened stems of the Calamitina type described 

 under different generic names, as Arthropitys approodmatiis' 

 and as Macrostachya'^. 



The determination of distinct species of the sub-genus 

 Calamitina is rendered almost hopeless by the variation in the 

 different branches of the same individual, and by the difficulty 

 of connecting surface-impressions with casts of the pith-cavity. 



A typical example of the Calamitina type of Calamites was 

 figured by Sternberg' in 1821 as Calamites varians. This has 

 been adopted by Weiss" as a comprehensive species including 



> Kenault and ZeUler (88), Pt. ii. PI. li. p. 423. 



- Lindley and Hatton (31), PI. cxiv. and PI. cxc. The original speci- 

 mens are in the Natnral History Mnsenm, Newcastle-on-Tyne. 

 3 Ibid. PI. cxxx. and Feistmantel (75), PI. i. fig. 8. 

 * Lesquereux (79), PI. xni. fig. 14. 



^ Salter (63), figs. 6 and 7. Vide also Carruthers in Woodward, H. (72), p. 168. 

 « Grand'Eniy (69) ; vide also (77) and (90). 



7 Benanlt and ZeiUer (88), Pt. ii. Pis. ui. and cm. ' Ibid. PI. li. 



s Sternberg (21), PI. xii. '» Weiss (84), p. 61. 



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