134 



FARMfc:RS' REGISTER. 



[No. 3 



From the Gardeners' Magazine. 



CONJECTURES EESPECTING THE CAUSES 

 WHICH PRODUCE DOUBLE FLOWERS IN 

 plants; TOGETHER WITH THE RESULTS 

 OF SOME EXPERIMENTS RIADE WITH A 

 VIEW TO THE SAME OBJECT. 



Jjij James Munro, Forester to the Marquess of 

 Northampton, at Castle j^shby, Northampton- 

 shire. 



Of the. various phenomena which nature exhi- 

 bits in her economy of the veoelable kingdom, 

 the cause which produces double flowers, and 

 Other singular varieties of plants, is, perhaps, least 

 understood by horticulturists. Different reasons 

 have been assigned for the presence of this liisus 

 nalurcB among vegetables; but, when even these 

 theories have been subjected to a practical test, 

 disappointment has Ibliowed. 



The prevailing opinion, in earlier times, rested 

 on the theory of contact; in other words, that 

 double-flovvering plants were a result from single 

 and double plants of the same kind grovvmg near 

 to each other; an erroneous assumption, that dou- 

 ble flowers possess impregnative qualities. Any 

 person, possessing the slightest knowledge of the 

 sexual system of plants,^knovvs that double flow- 

 ers are destitute of the productive org.ms; conse- 

 quently, no seed can be obtained from plants of 

 tiiis description: they are anti-natural, and are oc- 

 casioned by some infringement of the laws which 

 regulate the vegetable economy. How, then, is 

 it possible that plants thus physically incapaci- 

 tated lor self-reproduction, by seminal process, can 

 influence the character of their neio-hbors by the 

 mere circumstance of proximity? Besides, the 

 unalterable relation of the order of cause and ef- 

 fect is fatal to this theory; for, if the agency of 

 double flowers is required to alter tlie quality of 

 single-flowering plants of any kind, the question 

 arises. By what means did such flowers come to 

 exist at first? 



Of late years, it has been stated that Dr. Gra- 

 ham of Edinburgh gave it as his opinion, that, in 

 order to have double stocks, it is only necessary to 

 sow and rear the plants upon an exceedingly rich 

 soil, such as the pulverised material of old hot- 

 beds, &c. By this mode of treatment. 1 suppose 

 it is presumed that the plants shall receive such a 

 surfeit of alimentary matter as will cause a de- 

 parture Irom the natural way by which their va- 

 rious organs are formed, and their functions regu- 

 lated. The high authority whence this tlieory 

 was said to emanate secured it from me a fiiir trial; 

 but the experiment failed completely. My after 

 experience points out a cause of treatment the op- 

 posite to that of Dr. Graham. 1 have found that, 

 the more plants intended to save seed from are 

 checked in their luxuriance, the greater is the 

 chance of success. Every florist must have ob- 

 served that all the stunted-growing kinds of annu- 

 al stock are more productive of double flowers 

 than are the rambling-growing sorts; and that, in 

 both cases, the proportion of doubles is greater 

 from seed that is saved in an exceedingly dry sea- 

 son, when the growth is less luxuriant. From 

 this and other circumstances which have come 

 under my notice, I think there are grounds for 

 questioning whether the agency of any of the 

 afbre-mentioned theories is in the remotest deo;ree 



connected with the producing of double blossoms. 



The longer I consider this subject, the less I feel 

 disposed to trust in the eflicacy either of the theo- 

 ry of contact or of alimentary surfeit; the true 

 cause, I think, is more likely to be detected by pro- 

 perly tracing that striking analogy which subsists 

 between vegetable and animal creation. This 

 analogy is stronger than is generally supposed; 

 and, therefore, if we would arrive at correct con- 

 clusions regarding vegetable physiology, we would 

 do well to keep constantly in view the relative po- 

 sition which the subjects under consideration may 

 occupy in the scale of creation. Plants are depen- 

 dent on air and nutriment as well as animals: they 

 are furnished with numerous organs, suited aln^ost 

 to an animated existence; these are skin, pores, 

 glands, hairs, bristles, flesh, or fibre: they have 

 organs for respiration, with veins and arteries, and 

 a circulating fluid traverses the whole. This fluid 

 is at times held in excess by some trees; when 

 bleeding, or an operation equivalent thereto, may 

 be practised with propriety. Ringing the bark of 

 fruit trees, and shortening their roots to bring them 

 into bearing, are here alluded to; by which pro- 

 cess, if a copious discharge is not efl'ected visibly, 

 still a determination of sap to the head is prevent- 

 ed: this fluid adds annually to the bulk and strength 

 of the vegetable structure; which, as with ani- 

 mals, the belter it is led, the better it flourishes. 

 Nor does the analogy stop here: mutilations may 

 be healed or replaced; wounds and bruises may 

 be cured by ap|)!ications similar to those remedies 

 resorted to in cases of fractures of the anima! 

 frame. Cancerous substances and tumorous ex- 

 crescences may be excavated from trees as from 

 animals; and counter-irritations are successliilly 

 employed by gardeners, many of whom well know 

 the advantage of this process on trees technically 

 termed hide-bound. Slitting open the bark, in 

 such cases, produces effects on trees similar to 

 that of the blister on animals. It has likewise 

 been affirmed that excrementitious matter is emit- 

 ted from the roots; and scrofulous-looking tumors, 

 on some trees at least, are common. 



If due consideration be allowed to all these 

 close resemblances which the vegetable creation 

 bears to the animal, I trust I shall not be thought 

 extravagant in my ideas, if I endeavor to account 

 for the phenomena of vegetable variation by tra- 

 cing that analogy a step farther, and assign to 

 plants, as in animals, a plurality of fluidal sys- 

 tems. In animals, the diflerent fluids and humors 

 originate in one common source, the blood; in 

 plants, each system seems to have a direct com- 

 munication with the elements, and in their opera- 

 tions are independent of each other. It is evident, 

 from the manner in which its operations are con- 

 ducted, that there is one grand system employed 

 in forming the bark, leaves, and woody fibre; viz., 

 the albuminous current: it is also apparent that a 

 separate system exists in plants for the perfecting 

 of the fruit, which may be denominated the semi- 

 nal fluid; and it is highly probable that these sys- 

 tems are of a compound nature, each, perhaps, 

 furnished with organs for producing the properties 

 of color, taste, and smell, peculiar to each divi- 

 sion. If the progress of vegetation is watched 

 closely, we find that every tree, according to its 

 kind, "if raised in the natural way (that is, from 

 the seed), has its whole powers directed to the ac- 

 cumulation of wood, bark, and leaves, for a series 



