GENERAL RESULTS— PTEROPSIDA 657 



of other Coniferae, are cleared up (which is far from 

 being the case at present), it is useless to compare 

 these strobili with fossil fructifications. It appears prob- 

 able, however, that the comparison of the cone-scales 

 with Lycopod sporophylls, though seductive, may be 

 fallacious, the great complexity of the Araucarian cone- 

 scale suggesting that the resemblance is limited to 

 external characters. 



The absence of a pollen-chamber in the Coniferous 

 ovule is no doubt correlated with the abandonment of 

 fertilisation by spermatozoids. 



Without extending the discussion further, it may, I 

 think, be concluded that the Araucarieae have many 

 points in common with the Cordaitales, of sufficient 

 weight to establish a real affinity, while the resemb- 

 lances to the Lycopodineae are of a more doubtful and 

 superficial nature, and appear to be completely out- 

 weighed by the great differences which separate these 

 two groups. 



Since the Araucarieae ha^e been chosen as the family 

 most favourable to the Lycopod theory of Coniferous 

 descent, it does not seem necessary to discuss the question 

 for the other families. The idea that the Coniferae 

 include two wholly diverse groups, belonging to distinct 

 phyla, appears to me quite untenable — either all are 

 Lycopsida or all Pteropsida. The separatist view has 

 arisen from paying attention too exclusively to particular 

 organs rather than to the whole sum of characters. If 

 any group could be regarded as distinct in origin from 

 the rest it is the Taxaceae ; even here it is only the 

 morphology of the female fructification that presents 

 any serious difficulties, and in this very point a 



