April 3, 1889.] 



Garden and Forest. 



■65 



It is necessary that we should now glance at the structure 

 and the office of the flower ; that mechanism by which in the 

 plants which are called the higher, seeds are produced. 



The flower, for instance, in the case of flax, consists essen- 

 tially of a branch with leaves arranged in definite order, but 

 all so changed in their character that they are readily disdn- 

 guislied from ordinary foliage leaves. With the exception 

 of the outer circle of floral organs (which are frequently 

 much like green leaves), the parts of the flower are of very 

 delicate texture and possess some color unlike that of the 

 outer row. Within the highly-colored crown, or corolla, of the 

 flower, we come to the male organs of the blossom, known as 

 stamens, which consist of slender threads, each bearing at its 

 summit a minute sac filled with the fine grains of pollen ox 

 ferfilizing dust, by which the ovules (delicate roundish bodies 

 in the central organ of the flower) are to be impregnated. 

 The central organ, termed the pistil, bears the ovules in a 

 closed case, known as the ovary ,^\\\c\\ is surmounted by a 

 thread-like prolongation at the summit of which is the stigma, 

 a receptive sticky surface to which the pollen clings. 



The pollen, or male element of flowering plants, consists of 

 microscopic grains which vary considerably in size, shape and 

 sculpturing of the surface. The forms- and markings in a few 

 instances are so characteristic that they may be employed for 

 distinguishing large groups of plants, but in general the grains 

 are merely round or ovoid, and have ho very distinguishing 

 features. Pollen grains are either simple or compound, the 

 latter sort found in comparatively few species. One of the 

 most interesting forms of clustering of grains is found in the 

 milk-weeds and in the Orchid fannly, some of their clusters 

 being provided with minute stalks and sticky discs, by which 

 they can be carried by insects from one flower to another. 



A vast amount of pollen shed by some of our forest trees 

 and shrubs is scattered far and wide by the wind, borne, one 

 may say, at random, with only the merest chance of any of it 

 falling on the female flowers of the same species. And yet, as 

 matter of fact, it is waste with good results ; for out of the 

 prodigality successful fertilization is secured. It is a familiar 

 fact that the amount of pollen collecting on the shores of our 

 northern lakes is so great as to attract attention from the sul- 

 phur-yellow color which it imparts to the water. With the 

 pollen grains which collect on the shores there are generally 

 commingled the spores of some of our lower plants, notably 

 those of Lycopodium, or Christmas evergreen. These spores 

 are enveloped in a delicate filin of resinous matter, which 

 makes them water-proof for a long time, and causes them to 

 burn with a flash when they are brought into contact with 

 flame. In this way they can be distinguished from the pollen 

 with which they are mixed. 



At the opening of a flower, the pollen, borne in some 

 way, either by the wind or by insects, I'eaches the sticky stig- 

 ma, to which it adheres. After a variable time, there protrudes 

 from the pollen-grain a microscopic tube, containing proto- 

 plasm or living matter. This tube descends through the style 

 to the cavity of the ovary, where it comes into contact with the 

 ovule. For every ovule, there is supposed to be required, at 

 least in nearly all cases, one pollen tube. The ovule possesses 

 an intricate structure which, in its simplest form, may be said 

 to be a sort of minute vegetable egg (in fact, the word ovule 

 means this very thing), containing in one part a cell somewhat 

 larger than those surrounding it. This larger cell contains, as 

 do the other smaller ones, protoplasm or living matter, but 

 the protoplasm in this larger cell presents certain peculiarities 

 of form which need not be further described. It is sufficient 

 to say that one part of this protoplasm becomes affected in a 

 remarkable manner by the protoplasm in the pollen tube, and, 

 as a result of this action, the former begins to divide and sub- 

 divide, the other cells of the ovule undergoing changes, but 

 of a less remarkable character. The dividing contents of the 

 large cell of the ovule become sooner or later distinguishable 

 as forming the embryo or germ, and associated with this is 

 a certain adequate amount of food, all being enclosed in the 

 hardening ovular coats, which become the integuments of the 

 seed. 



Unless the ovular protoplasm is acted upon by the contents 

 of the pollen tube, the globular body withers away and comes 

 to nothing. Contact of these two diverse elements is requisite 

 to the formation of the germ within the seed. There are a 

 few anomalous cases known as those of parthenogenesis , in 

 which germs appear to be produced without the action of 

 pollen, but these are so very exceptional that they may be dis- 

 regarded in the present treatment of the matter. 



After the seed begins to ripen, concomitant changes take 

 place in the ovary, the whole ripening into the fruit. The fruit 

 may be defined as the ripened ovary; the seed may be called 



the ripened ovule. In the ripening of the fruit there is gener- 

 ally more or less change in the neighboring parts, and these 

 modified parts may become conjoined to make what is popu- 

 larly called the fruit. For instance, the Strawberry consists of 

 a thickened pulpy stalk, which has acquired sweetness and a 

 delicious flavor. Upon this rounded or conical fruit-stalk are 

 borne numerous ripened ovaries, which seem so much like 

 seeds that until one cuts them open he is unwilling to believe 

 that each is a fruit-case holding a seed. 



Ripened seeds and fruits bear some curious relations to each 

 other. For instance, it is rare to find any ovary containing 

 more than a couple of seeds, which is incapable of opening 

 and discharging some of its seeds. On the other hand, fruits 

 which have only one or two seeds are very apt to remain 

 closed even when they are " dead ripe." The bearings of 

 these relations on the manner of dissemination can be easily 

 thought out by any observant person who will note the differ- 

 ent sorts of fruits and the numerous contrivances which they 

 possess for distributing their seeds. In connection with this 

 it should be said that one-seeded fruits are often furnished 

 with some means for dissemination, such as by wings, plumes, 

 hairs, hooks, claws and the like. 



If one were to examine the flowers of our common forest 

 trees in the hope of finding such flowers as we have described 

 in the case of the flax, he would be disappointed. A few 

 have showy blossoms, like the Magnolia, Tulip-tree, and 

 Catalpa, and, among shrubs, Rhododendron, Azalea, and 

 so on, but these are exceptions. Most of our trees have 

 flowers which are very much reduced in numerous par- 

 ticulars, but all of them agree in this : that they contain 

 either the male organs, the pollen-bearing stamens, or else 

 the female organs, the pistils with their ovules, or in very 

 many cases, both of these in the same flower. But the flowers 

 of trees at the North are, as a rule, brought down to very nar- 

 row limits as regards color and complexity. Nevertheless, 

 since they possess the essential elements of the flower, they 

 can produce seeds with germs, and hence carry on that form 

 of reproduction by which variation is introduced into the line 

 of succession. 



In conclusion, it may be said that a seed is an embryo plant, 

 supplied with a sufficient store of food and provided with a 

 protecting case. It has also been given some means by which 

 it may be carried to some distance froin the parent plant, thus 

 lessening competition. 



Cambridge, Mass. George Lincoln Goodale. 



The Forest. 



Forestry in California. 



THE following extract is taken from the last report of 

 the California State Board of Forestry. The report 

 was prepared, we believe, by Mr. Abbot Kinney, of whose 

 efficient services the state has recently been deprived: 



The debris of the hydraulic mines in this state is infinitesi- 

 mal and harmless in its damages compared to what must oc- 

 cur if the high Sierras are unduly denuded of their forest 

 covering. In such case the rains must flow off more rapidly 

 and the snows melt more suddenly than at present. Thus the 

 perennial value of the streams for irrigation must diminish, 

 and sudden and destructive floods are certain to occur. The 

 histories of such countries as Palestine, Persia, Greece, Nordi 

 Africa, Spain and the south of France demonstrate the results 

 of unwise forest extinction, especially upon the mountains. 

 That California will prove no exception to the rule is shown 

 bytheinstancesof the diminution of springs and streams, and by 

 the formation of torrents in this statedue to forest destruction, 

 collected and presented with time, place and witnesses in our 

 last report. Now that these mountain water-sheds in forests 

 so important to the irrigators, farmers and consequently to all 

 persons in the state have generally passed into private hands, 

 there seems but one way left to deal with the question. This 

 way is by education of the people, to demonstrate that a waste- 

 ful and unscientific destruction of forests upon certain critical 

 points of important water-sheds, while temporarily beneficial 

 in a gain of a few thousand dollars to some individuals, 

 threatens the loss of millions of dollars of property to others. 

 Thus the carelessness or improvidence in the mountains of 

 one man may destroy the property and means of livelihood of 

 thousands of his fellow citizens in the valleys below. This 

 point established, legislation in the line of the forestry laws of 

 other experienced and civilized countries can be had. We 

 will then have a reasonable regulation of lumbering methods, 

 upon important water-sheds of the state, with a view of pre- 

 serving the integrity of our springs and streams for the pro- 



