216 PHILOSOPHICAL NOTES OX 



sporangia of the vascular cryptogams in the mode of their 

 development. A section through the pollen-sac of one of the 

 Cupressineae, for example, shows that itresembles a sporangium of 

 Lycopodiumr And, at p. 515, he states that " Goebel draws 

 attention to the fact that in the majority of the Cupressineae the 

 pollen-sacs are protected by an outgrowth of the staminal leaf, 

 which he considers to be analogous to the indusium of Ferns." 



It was gratifying to meet with opinions such as these 

 regarding the anther, for in stud}dng cryptogamic plants I had 

 come to the conclusion that in them we find the rudiments of 

 many of the parts of higher plants. 



On p. 541, Sachs truly says, regarding the nature of the 

 stamen, " that it cannot be arrived at by a study of development 

 alone, but comparisons must be instituted," and even in some 

 cases the " phylogenetic method " must be followed. 



I certainly agree with him. His conclusion is not only 

 reasonable, but very important. However instructive micro- 

 scopical and histological observations may be, we should not 

 forget that in evolution, cells are as likely to abort and disajDpear, 

 while others in a state of dormancy may come to the front and 

 take the lead, just as whole parts of a plant sometimes do. 

 Histology alone, therefore, dealing as it does with cell-develop- 

 ment, is insufficient to discover homologies. Moreover, it 

 bewilders and confuses the mind with innumerable new names, 

 without making the nature and homology of an organ much 

 clearer, and without bringing us any closer to the solution of 

 the main question. This, in my opinion, is — what relation the 

 different parts of a plant, as we see them, bear to each other, and 

 what relation the parts of the higher plants, which are so 

 conspicuous, bear to those of the lower and lowest which are not 

 so conspicuous ? The solution of this question would enable us 

 to mentally grasp plant evolution as a whole, and thus form some 

 conception of the transition between the unicellular and the 

 myriads of multicellular components of the vegetable world. 

 What we are all aiming at, I should say, is to understand, in 

 some measure, how this vegetable creation we see around us has 

 been brought about, by the process called evolution. 



In Abies Pectinata (Sachs, Fig. 350) and in Asarum 

 Canadense (Fig. 358) each stamen with its pair of dorsal anthers 



