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appearance. Looking at this receptacle from another point of view, we 

 shall find it to be composed of a central axis, which divides out into 

 short processes that bear the reproductive organs. This is their essential 

 function in common with that portion of the axis included between their 

 bases. These axial processes in the present instance are not isolated, 

 but united together ; so that, looked at from without, only an oval body, 

 pierced with pores, is observed. 



Development, however, is accompanied by the division and separa- 

 tion of parts. This we may suppose to happen here by the gradual 

 isolation of the axial processes already mentioned. The united exterior 

 of the receptacle is split up by fissures, running from pore to pore, as 

 imagined in Fig. 2 ; and we have then the axial processes isolated from 

 each other and distinct. What was essential with them — the bearing 

 of the reproductive organs — remains constant ; though these, instead of 

 being spread over the whole interior surface, may be restricted to par- 

 ticular parts. 



The division and isolation spoken of do not take place in the Eucaceae. 

 We must look for it in a higher order, and shall readily discover it 

 in the strobilus of the Equisetacese. In Eig. 3 we have a vertical 

 section of this cone. Considered in this light, its affinities with the re- 

 ceptacle of the Eucus become obvious, and scarcely require to be pointed 

 out. Everything remains the same, except that the spores are not dis- 

 persed over the whole interior of a conceptacle, but restricted to the 

 inner rim of the peltate head of the axial process. Of course, as these 

 processes aT-e isolated, a view of the exterior of the perfect cone does 

 not show pores, but fissures. In point of fact, it is identical with the 

 fissured receptacle as imagined in Eig. 2. 



Having arrived at this stage, the next modifications are accomplished 

 by simple changes in the axial processes, taken by themselves, or with 

 regard to the axis. In the first instance, the receptacle is wholly cel- 

 lular, as is the plant which bears it. Some difference has been observed 

 between the laxer cell tissue of the centre and the denser parenchyma 

 which surrounds it. In more highly organized plants a similar rela- 

 tionship is preserved between the axial and the peripherical tissues. 



Passing from the preceding examples to Eigs. 4 and 5, we come 

 to explicable developments of those forms in the higher order of 

 the Pinacese. In the first-named figure we have a vertical section of 

 a galbulus (of Cupressus semper vir ens) ; in the second, a similar sec- 

 tion of the strobilus or cone (of Pimm sijlvestris). In the galbulus the 

 axial processes are not so remote in form from what we have seen them 

 in the cone of Equisetum as not to allow of the relationship being re- 

 cognised without difficulty. Here also they are peltate ; and the only 

 remarkable difference is, that the ovules are not borne exactly in the 

 same spot as the spores, but a little removed from it. This, however, 

 was mentioned as to be expected.* In the Pine cone (Eig. 5) the axial 



* These female cones are strictly analogous to the ovaries of Angiospermia, being in 

 fact ovaries. Considering them as such, it is interesting to note that the diverse distri- 



