1883.] 



AND HORTICULTURIST. 



begins. Sometimes wc may bt.' able to tell with 

 considerable certainty the age of a tree from its 

 "annual rings," but many trees will not give it ac- 

 curately, and we arc not sure but those which seem 

 to give us the data with considerable regularity, 

 often vary from their plan. 



In the cut will be noted some features which we 

 do not remember to have ever been referred to by 

 those elementary works which treat of the forma- 

 tion of wood. It will be noted that the outline 

 given by the bark is formed of segments of five 

 circles, and that the bark is of double the thickness 

 and forms a parallelogram where these segments 

 meet. These rectangular blocks of bark are op- 

 posite the bays in the star formed by the pith in the 

 center. The' center of the arm of the star corres- 

 ponds to the center of the arc in the outline of the 

 wood. From each sinus in the star to the rectan- 

 gular blocks of bark, are two nearly parallel lines. 

 The whole piece of wood is thus divided into five 

 sub-triangular segments. The little "hair lines" 

 crossing the two parallel ones, do not connect with 

 the lines enclosed by the triangle, but they are uni- 

 form in number with them. 



It would be foreign to our present purpose to go 

 into any explanation of the morphological interpre- 

 tation of the pentamerous plan on which the trunk 

 of an oak tree is seen to be formed. All we have 

 room for is to give a brief explanation of what the 

 "hair lines" mean. There has been a great deal 

 of unnecessary mystery thrown around the forma- 

 tion of wood. We are told about the annual con- 

 centric " layer" of wood, and the cambium "layer," 

 and other " layers," as if a new plaster of material 

 was placed over the old wood, which in time be- 

 came a solid layer stuck over the old one. The 

 idea is much as we might gather ffom the making 

 of a candle. The wick is first dipped into the 

 molten fat, then drawn out to cool — then dipped in 

 and out again, every time getting larger by the ac- 

 cretion of the cooling liquid. But wood is not 

 made in this way. There is no evidence that any- 

 thing which has life came directly from inorganic 

 elements. That which is alive came from that which 

 had life before it. All things spring from an egg, 

 and the cells out of which the trunk of a tree is 

 formed are no exception. Every living cell sprung 

 from a parent cell, and the cells out of which this 

 season's wood is formed, came in a direct line from 

 the cells of the year before. The mass of mucilage 

 between the bark and the wood, called by Grew 

 " Cambium," and which is supposed to generate 

 the cells which are to form a new " layer" of bark 

 and wood, does nothing of the kind. It furnishes 



simply food for the new cells which push out from 

 the mother cells just behind them. Now the 

 "hair lines" in the cut show the successive 

 generations of these cells during the growing 

 season. In our piece of two year old wood, there 

 are twenty-four concentric circles in the year in- 

 stead of merely "one annual layer," in the sense in 

 which this expression is usually understood. 



We have purposely avoided in this little sketch, 

 using the language of science to describe this pro- 

 cess of forming the annual growth of wood. The 

 object is to convey to those who are unacquainted 

 with this language, some idea of what they may 

 know more about if they care to pursue the study 

 further as a matter of science. 



M.\LK .A.ND Fkmalk Flowkrs. — The especial 

 purposes for which the division. of all living things 

 into separate sexes was designed, has been stated 

 by the writer of this in former writings and dis- 

 courses, to be evidently as part of the plan which 

 makes continuous variation lie at the bottom of the 

 continual growth of new species in the world. 

 Further, the writer has shown that the law which 

 operates to produce the separate sexes, is in close 

 alliance with nutrition. There have been enough 

 illustrations given to show that the rule is for the 

 female flowers to be placed where they are the best 

 nourished, and just in proportion as the amount of 

 nourishment to any particular part of a plant pre- 

 vails, will the number of female flowers in that part 

 excel. 



It is always, however, the part of the true 

 searcher for truth to make as prominent observa- 

 tions which seem to oppose his conclusions as 

 those which do. Usually in begonias we find the 

 rule prevail which we have indicated — that is, the 

 male flowers appear on weaker stems than do the 

 female. But we have now a species which seems 

 to go on the contrary side. The female stems ap- 

 pear much weaker than the male ones. The female 

 ones can be readily seen by the young seed vessels 

 which are placed at the base of the petals. The 

 male flowers have no such protuberance. A sep- 

 arate male and female flower is given, enlarged, 

 at the base of the picture, the larger one with the 

 numerous anthers in the centre being the male, 

 and the smaller, with the pistils in its centre, being 

 the female. 



We have not yet had a chance to sec this species 

 in cultivation. It was introduced recently by 

 Messrs. J. Veitch & Sons, who say of it: 



" Begonia Socotrana, a species of remarkable in- 

 terest both in its scientific and in its horticultural 



