CHEIROSTROBEAE 



117 



sterile ; the three superior segments were the fertile 

 sporangiophores, while the three inferior members were 

 sterile bracts. 1 The two kinds of segments resemble 

 each other in their stalks, which are long and slender 

 in both, but differ in the form of the laminae in which 

 they terminate at their distal extremities. 



Fig. 50. — Cheirostrobus pcttycurensis. Part of radial section, showing the peltate 

 sporangiophores, s, with the foliaceous sterile segments, /, between them. The lowest 

 sterile segment shows the form of the lamina well. The sporangia are seen to the 

 right. X about 10. Phil. Trans., S. Kidston Coll. 87. 



The fertile segments or sporangiophores had each 

 a thick peltate lamina, much like that of an Equisetum 

 or C alamo stachys, bearing four sporangia on its inner 

 side (see Fig. 49, f, and Fig. 50, s). The sporangia 



1 This latter point was not determined without difficulty, as the same 

 segment can rarely be traced from end to end, but is now settled beyond 

 doubt. 



