AND GENERAL HOBTICUIiTUKE. 



197 



HYB 



Hybridization. It is to the careful, system- 

 atic, and pains-taking efforts of tlie hybridizer 

 that most of our "Florist's Flowers" have been 

 brought to their present standard of excel- 

 lence. The operation consists in removing 

 the pollen by means of a camel's hair brush 

 or otherwise, from the male parent and placing 

 it on the stigma of the female or seed bearer. 

 Of course unless the latter is receptive this 

 proceeding would be ineffective. As a rule 

 when the stigma is fit to be acted upon by the 

 pollen, it becomes more or less glutinous. 

 This condition occurs in some plants before 

 their own anthers are ready to discharge the 

 .pollen, and in others after the pollen has been 

 shed. In both these cases, the arrangement 

 is evidently to prevent self-fertilization. In 

 most plants however the stigma and anthers 

 are developed at the same time, and with 

 them it is necessary to remove the anthers 

 before they burst, and at the same time by 

 means of fine gauze or otherwise to prevent 

 the visits of insects which might convey pollen 

 from another flower and thus effect an undesir- 

 able cross. Insects doubtless perform an 

 important part in the fertilization of flowers, 

 for upon examination a number of plants will 

 be found to bear flowers manifestly adapted 

 for insect visitation. Not to mention the 

 Orchid family which ' Darwin observed so 

 closely and has described so minutely, the 

 curious genus of Stapelia is fertilized solely 

 by the larvee of a fly, generally the common 

 "Blue Bottle."- This fly, attracted by the 

 offensive odor of the flower, lays its eggs 

 as far as it can in the tube of the corolla. 

 These eggs hatching, the larvae they produce 

 come in contact with the pollen-granules 

 which adhere to them and which they carry to 

 the pistils and thus fertilize them. A similar 

 office is performed for Ceropegia by a small 

 fly in the perfect state. As a rule, flowers 

 possessing much fragrance, and secreting 

 nectar, and those of gay colors, are more or 

 less dependent on insect agency. Herma- 

 phrodite flowers, being provided with both 

 stamens and pistils, pollen and ovary, one 

 would suppose to be amply furnished with the 

 powers of reproduction, yet it has been abun- 

 dantly shown that flowers fertilized by 

 themselves do not produce such vigorous and 

 healthy seeds and offspring as those fertilized 

 by another flower of the same species ; hence 

 the disadvantage of breeding in and in, the 

 nearer the degree of consanguinity, the less 

 prospect is there of healthy and vigorous off- 

 spring. The hybridizer therefore finds a 

 flower of good shape but defective in color, 

 crosses it with another, defective perhaps in 

 shape but of a novel and desirable color, a 

 weakly growing variety of good habit, is cross- 

 ed with a more robust variety, lacking the 

 peculiar qualities of the former and so on. 

 With regard to Double Flowers, if theflnest 

 colored and best shaped flowers of the single 

 sorts are selected as in the Petunia, the 

 anthers carefully removed before they burst, 

 and then fertilized with pollen from the best 

 double or even semi-double flowers attainable, 

 fifty to seventy -five per cent, of the progeny 

 may be relied upon to produce flowers equal 

 to, and often superior, to the parent. In a 

 lecture before the Massachusetts Horticultural 

 Society, the Hon. Marshall P. Wilder, a most 

 successful hybridizer, said, " In my experi- 



HYD 



ments, I have discovered that for the pro- 

 duction of double flowers, it is important that 

 the pollen used for impregnation should be 

 borne on a petaloid anther — ^that is, an anther 

 bearing a small petal — and that this is still 

 better if from a double flower. I also observed 

 that the larger and better developed this 

 petaloid anther, the better chance for a fine 

 double offspring; for as might have been 

 expected, the anthers being connected with 

 the corolla, the number, of petals would be 

 increased by such an operation. I found also 

 that for the most perfect and symmetrical 

 flowers, it was better to select single flowers, 

 which were the most perfect in their petals 

 for seed bearers ; and that single or semi- 

 double sorts with perfect corollas, when 

 impregnated with petaloid pollen, will pro- 

 duce double flowers of a regular symmetrical 

 formation. Of this I have the most conclu- 

 sive evidence in the Camellia WUderii, and 

 many other fine double varieties in my col- 

 lection which were produced from a single 

 red and single white Camellia, fertilized by 

 pollen from a petaloid anther of double 

 varieties." Mr. Wilder for many years made 

 the hybridization of Camellias a speciality and 

 to his efforts we owe some of the best vari- 

 eties in cultivation. 



Hydra'ngea. From hydor, water, and aggeixm, 

 a vessel ; referring to the cup form of the cap- 

 sule or seed-vessel. Nat. Ord. SaxifragacecB. 

 A genus of showy shrubs, first introduced 

 into England in 1790 by Sir Joseph Banks, 

 who sent H. hortensia from China, and since 

 then a number of species have been sent to 

 this country from Japan, among which is a 

 climbing variety, H. volubilis, or scandena, 

 that will adapt itself to almost any situation. 

 It is slow growing and a little tender while 

 young, and is still scarce. What has been 

 known as the climbing Hydrangea, will be 

 found described under Schizophragma. The 

 flowers, or rather bracts, of H. hortensis are 

 pink, but in some soils they become of a deep 

 blue. This change is effected artiflcially by 

 using iron fllings, incorporating them in the 

 soil. A distinct white variety of H. hortensia, 

 known as "Thos. Hogg," is now very popu- 

 lar. To cultivate these plants in perfection, 

 cuttings should be taken every season from 

 the strongest shoots of the old plants in July 

 or August ; and after being struck, should be 

 potted in rich earth, and encouraged to grow 

 vigorously. A cold pit or frame, with fre- 

 quent applications both of manure and plain 

 water," will usually effect this, and cause them 

 to become thoroughly established and strong 

 before the winter. In this state they may 

 either be forced in a gentle, moist heat 

 through December and the spring months to 

 bloom early, or kept cool for the production 

 of summer flowers ; in either case, it must be 

 borne in mind that they require abundance of 

 moisture when in an active state. H. pani- 

 culaia grandiflora, introduced a few years 

 since from Japan, is among the finest of all 

 hardy shrubs for the lawn or the border. The 

 flowers are white, and are produced in the 

 greatest abundance in August, and remain, 

 till mid-winter in a dried condition. H. 

 Otaksa, also recently introduced from Japan, 

 is of the habit of H. hortenais, but a stronger 

 grower, and more profuse bloomer, forming a 



