656 STUDIES IN FOSSIL BOTANY 



character diagnostic of the class. 1 The numerous 

 nuclei in the pollen-tube of the Araucarieae present 

 a manifest analogy, as Professor Seward recognises, 

 with the multicellular antheridia of Cordaiteae and 

 Pteridosperms. At present we know nothing of 

 the fertilisation of the •' seed-bearing " Lycopods, so 

 on this side the material for an equally close com- 

 parison is wanting. 



The female cones of the Araucarieae alone appear 

 to afford any real support to the Lycopod theory. The 

 single ovule on the upper surface of the cone-scale 

 offers an evident analogy with the sporangium and 

 sporophyll of a Lycopod, though, if the Cretaceous 

 Protodammara, with three ovules on each scale, is 

 rightly referred to Araucarieae (p. 607), the value of 

 the analogy becomes very doubtful. In any case the 

 vascular system of the Araucarian cone-scale is totally 

 different from anything in the sporophylls of Lycopods. 

 The comparison between Araucaria, in particular, and 

 Lepidocarpon, on which Professor Seward lays stress, 

 appears to amount to no more than a distant analogy, 

 for the part which envelopes the ovule in Araucaria 

 is not, as in Lepidocarpon, the integument itself, but 

 an extra covering enclosing an already integumented 

 megasporangium. 2 



Until the nature of the so-called ligule, and, generally, 

 the relation of the female cones of Araucarieae to those 



1 The comparison of the Araucarian stamen with the sporangiophore of 

 Cheirostrobus, suggested by Professor Seward, is interesting, but by no 

 means supports a relation to the Lycopods, with which Cheirostrobus can 

 only have a remote affinity. The point is dealt with in the discussion on 

 the "Origin of Gymnosperms " above referred to, pp. 143 and 147. 



2 See Figs. 25 and 26, p. 362 of Seward and Ford's Araucarieae. 



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