August 14, 18G«. ] 



JOURNAL OF IIOHTICULTURE AND COTTAGE GARDENER. 



117 



WEEKLY CALENDAR. 



ON THE VARIEGATION AND CROSSING OF 

 PELARGONIUMS. 



>e a curious 

 and difficult subject taken 

 up with the earnest and 

 fresh-minded enthusiasm 

 of Mr. Wills. Years of close 

 observation and close rea- 

 soning, however, combined with scientific accuracy, have 

 yet to be gone through before he or any one else can throw 

 much light upon this mysterious subject. 



Until of late, when the taste for variegated plants has 

 provoked experiment, variegation was supposed to be non- 

 transmissible by seed, and this must still be considered the 

 rule, and the contrary the exception. It is probable that 

 most of our variegated Geraniums are sports, but it is cer- 

 tain that some have been raised from seed : to what extent 

 I know not, but I have raised several myself, which were 

 symmetrically marked from the seed leaf to the perfect 

 plant. It is much to be desired for the interests of science 

 that the originators of these variegated Geraniums should 

 come forward and state their origin. Trade secrecy in 

 these matters is in these times happily ignored by our high- 

 caste nurserymen, now a highly educated and intellectual 

 class of men, and I hope tliis appeal may not remain long 

 unresponded to. Amongst other curious assertions is the 

 following — viz., that a green-leaved sport from a variegated 

 plant will again sport, but into a fresh form of variega- 

 tion — golden, for instance, instead of silver. This wants 

 confirmation, 



With legard to Mr. Wills's seedlings, I do not think 

 foreign pollen had necessarily anything to do with the 

 matter, as the same phenomenon occurs when the accuracy 

 of the experiment has been actual. Moreover, whether 

 the variegated plant be the male or female parent, much 

 the same per-centage of green and of variegated plants will 

 appear. The strength of constitution is always in inverse 

 proportion to the variegation, being greatest in mottled and 

 irregularly marked plants, less in the rarer case of sym- 

 metrical or true variegation, and nil in the ease of pure 

 albinos, which I have never known to perfect a rough 

 leaf. On examining a large number of seeds of Flower of 

 the Day many years ago, I observed fair types of seed — 

 viz., robust green, striped green, colourless, and a modified 

 or brownish green. The green seeds produced green plants ; 

 the striped, often seedlings of which one cotyledon was 

 green anil the other white ; the colourless seeds came white ; 

 while the fourth description produced plants variously 

 marked with white, and occasionally true variegations at 

 once. The mottled plants threw true variegations from 

 the part of the stem just above the place where the coty- 

 ledons existed, as observed by Mr. Wills. The green ones 

 No. 281.— Vol. XI., New Series. 



remained green, but would probably have sported sooner 

 or later. 



The striped form of colour is a very curious subject, and 

 well worthy of observation. Tin; stripe may be traced 

 running up through (lie stem from its origin, through the 

 flower-stem, thence to the pedicel and bract, and finally 

 into the seed itself, sometimes affecting two or three 

 pedicels in a group, sometimes striping a single pedicel. 

 Symmetrically-marked shoots never appear on a striped 

 branch, in which case they are cither green or white en- 

 tirely, as far as I have observed. In the lower and more 

 ripened part of the stem the two colours seemed to be more 

 fused, and disposed to an equal development. There is 

 also a visible difference in colour between wood which is 

 likely to throw variegation, and such as will develope itself 

 in purely green growths. 



In some early experiments of my own I found that the 

 pollen of Golden Chain tinged the seedlings of green- 

 ibliaged plants plentifully witli different shades and mark- 

 ings of yellow. The per-centage of such seedlings was 

 rather large, and one came perfectly variegated from its 

 birth. When this is the case the cotyledons are striped 

 with the yellow or white colour down the midrib of each. 

 The plant alluded to was a slow grower. I gave it to a 

 friend in the nursery business, and never heard what be- 

 came of it. 



With regard to the pollen question, there is a great 

 difference in plants as to their capability of becoming 

 fertilised by the pollen of other plants in their neighbour- 

 hood ; some seem absolutely to refuse it, while oilers can 

 hardly be kept true when this, as in culinary plants, is 

 desirable. The Geranium, certainly, when placed in prox- 

 imity with other Geraniums, is liable to he fertilised by 

 their pollen, and this, when one would think they could 

 scarcely escape the influence of their own. Of the agency 

 of insects in this matter there can be no possible doubt. 

 On the other baud, I am now working at a genus of plants 

 profusely supplied with pollen, which I grow in large 

 numbers under glass, and in the course of five years have 

 never observed an accidental hybrid. Whether fertilisation 

 is effected to any great umount by floating pollen under 

 glass I do not know, but I may suggest the following nearly 

 crucial experiment: — Wet ■,: pane of .lean glass with gly- 

 cerine, wave it in the supposed pollenised air, or let it 

 remain there for some little time. The presence of pollen 

 grains may then be easily detected under the microscope. 



The electrical question is altogether too deep for me, 

 although not a new observer. Such matters call for a 

 peculiar line of investigation by very experienced hands, 

 upon rigidly accurate principles, carried out with pre- 

 viously-acquired and real knowledge of the subject. The 

 contrary leads to burying electrical wires in Wheat fields, 

 and printing great resin's which occurred in consequer 

 the feat, without recording the quantity of manure p 

 nt i!i ■ ing any one phenomenon of any 



kind occurring between the seed time and harvest of the 

 experimental crop. 



As an old hybridise;-, I will venture to suggest to Mr. 

 Wil and other labourers in tin- field, to work upon bat 



No. 933.— Vol. XXXVI., Old Series. 



