350 MORPHOLOGY. 



on the back of which arise a number of little cellular masses, and these 

 become (sessile) capsules in which the pollen grains are developed. 

 That the foliar organ is here developed into a woody scale is an 

 inessential matter of subordinate importance. A similar structure would 

 not be impossible in a Fern, but would merely give a generic distinc- 

 tion. Thus, in Cycas we have all the essential characters of the sporo- 

 phyll of the Fern ; and Cycas would be a Fern, if a strict boundary were 

 not drawn by the peculiarity of the development of the spore (or pollen 

 grain) into a plant. In the same way, and in a still higher degree, holds 

 the analogy between the stamen of Taxus and the sporophyll ofEquisetum. 

 Disregarding the remnants of the parent-cell, which in the latter adhere 

 to the spore, not even a generic distinction could be drawn between the 

 two structures, if the development of the pollen grain in the seed-bud in 

 Taxus did not again enter into the question. The capsule at the base 

 of the leaf of Lycopodium also corresponds naturally to the three anther- 

 cells of the base of the leaf in Cunninghamia sinensis, Rich. That the 

 latter are formed on the under, the former on the upper, surface of the 

 leaf, can make no essential distinction with the frequent exchange from 

 anthera antica to a. postica in the same family. If we then trace the 

 stamens from Cycas through Zamia, Araucaria, Agathis, Cunning- 

 hamia, and those of Taxus through Juniperus, Thuja, and Phyllocla-r 

 dus to Pinus, we find in both series a gradual transition to a simple 

 form, which then becomes the fundamental type for all the rest of the 

 Phanerogamia, and may at once, by comparison, but more safely still by 

 following out the development, be traced back in a definite manner to the 

 modified stem -leaf. This phanerogamic type consists merely of this: 

 that the two lateral halves of a leaf, at the sides of the mid-rib (the con- 

 nective), develope into chambers, in which two groups of parent-cells, 

 separated by a layer of cellular tissue, form pollen, so that every anther 

 is typically an anthera bilocularis, quadrilocellata. I shall have to speak 

 more at length regarding the apparent deviations from this structure in 

 the following paragraphs ; in this we have merely to do with the definition 

 of the idea and the external form. 



The last point requiring notice relates to the differences of the external 

 form of the stamen. I have here, as in all other cases, confined myself 

 to the indication of the outline of the directions which these subordinate 

 variations of form may take. Here, again, the different denominations 

 of the forms are not signs of different ideas, but serve for empirical 

 description, and therefore are to be understood as pictorial expressions, 

 according to the meaning of the words ; they are therefore by no means 

 fixed things in the science, but undergo constant extension and correc- 

 tion, as the art of observation and empirically describing, in science in 

 general, becomes developed, or as an individual gifted with a special talent 

 for this advances it. No Botanist is tied down to such terms as cucullus, 

 calcar, appendix, &c., when once he hits upon an expression which 

 describes these forms more aptly, and in accordance with the impression 

 they make ; and no confusion in science can arise from this. It does, 

 indeed, bring confusion into science, and makes a scientific unity in 

 nature altogether impossible, when a Botanist applies the same terms to 

 fundamental and derivative forms ; for instance, to actually independent 

 foliar organs and to their appendages, since here the question is no 

 longer a more or less perfect success in conveying the impression, but a 

 confusion of the definitions deduced from the essential nature of the 

 object. 



