GALLESIO'S TREATISE ON THE CITRUS FAMILt. 



plants willi single ilowcrs. This experiment was 

 continued in the i'ollowing manner: I chose 

 plants of semi-double llowers. and fecundated 

 them with the pollen of other semi-double 

 llowers. Several others of semi-double llowers 

 were left untouched. The seeds from the fecun- 

 dated flowers produced roots bearing for the 

 most part double llowers, crowned often in the 

 middle by a tuft of green leaves which rendered 

 them very pretty. The seed from the Ilowcrs 

 not fecundated, although already semi-double, 

 gave only plants bearing single flowers. I re- 

 peated this experiment for several years, but 

 always with the same result, and a similar ex- 

 perience with other llowers gave also the same. 



Experiment VLL fecundated the llowers of 

 the orange with the pollen of the lemon tree, 

 and I obtained a fruit whose skin was cut from 

 end to end by a stripe yellow and elevated, hav- 

 ing the characteristics of the lemon. The taste 

 of the fruit was entirely that of the orange. It 

 had few seeds, and these small and poor. 



Experiment VII. I fecundated the flowers of 

 an orange tree with the pollen from several other 

 orange trees, and obtained several times fruit 

 whose pericarp had an irregular form, containing 

 few seeds and those very defective. 



Experiment VIII. I sowed orange seeds 

 whose flowers had been fecundated, and whose 

 pericarp had suffered no change ; and obtained 

 plants which do not yet bear fruit, but one of 

 them is devoid of spines, and another displays a 

 very vigorous foliage, which distinguishes it from 

 ordinary orange trees. 



METHOD PURSUED IN ARTIFICIAL FECUNDATION. 



The procedure which was employed in the ar- 

 tificial fecundation is simple, and indicated by na- 

 ture herself. 



I chose the ripest and most highly colored pol- 

 len from the most thrifty flowers, and those most 

 nearly ready to bloom, and applied it to the pistil 

 of the flower which I wished to fecundate. In 

 order to render the operation more exact, I de- 

 tached the flower from its stem, and having de- 

 spoiled it of corolla,! rubbed the anthers without 

 touching them, upon the stigma to be fructified. 

 This operation was repeated with several differ- 

 ent flowers, without depriving the flower sub- 

 mitted to thQ operation of its stamens. I took 

 care to repeat it several times each day for sev- 

 eral days. This precaution was necessary in or- 

 der not to miss the moment of "blooming in the 

 pistil which was to receive the pollen, and to as- 

 sure myself by means of a quantity of this pollen 

 taken from different flowers, respecting its dis- 

 position to exercise its fecundating dualities. 



In the flowers of the orange tree the moment 

 of maturity for fecundation seems to be an- 

 nounced by the appearance of a honey-like drop 

 which forms on the stigma of the pistif,aud serves 

 to retain the dust applied to it ; and the same 

 maturity in the pollen is indicated by the deep 

 yellow color it then assumes, and by its quality 

 of adhering to the finger when touched ; but it is 

 also necessary to be careful to multiply the exper- 

 iments, because often after having fecundated 

 several flowers as one may suppose, none, or but 

 lew, may be successfully operated upon. But 

 success is more certain with the ranunculus and 

 carnation. 



CONSEQUENCCS. 



itcel. Mixed fecundation operates in 

 various ways upon vegetables. It may act upon 

 the ovaries or upon the ovules. (Exp. V., VI., 

 VII., and VIII.) When it acts upon the ovaries 

 the pericarp of the fruit which has been fecun- 

 dated receives modifications, and bears but few if 

 any seeds. (Exp. VI. and VII.) When the ac- 

 tion is upon the ovules the fruit which encloses 

 them does not seem affected by it, but these 

 ovules grown into seeds give sonic trees which 

 do not resemble the parent tree, and most fre- 

 quently have a tendency to sterility. 



This tendency to sterility determines itself in 

 different ways ; sometimes upon the flower, when 

 we have plants with double, or semi-double, or 

 possibly with simple and sterile flowers ; some- 

 times upon the fruit, when we have plants with 

 sterile or semi-sterile fruit, for these fruits either 

 bear no seeds, or very few, and those badly nour- 

 ished. In all cases these species of mules or hy- 

 brids show unusual vigor in the thrifty branches 

 free from spines, or in the better nourished leaf, 

 or the flower with multiplied petals, or the fruit 

 of more beautiful pericarp. These characteris- 

 tics especially distinguish the greater part of the 

 beautiful varieties ; hence the varieties are due 

 only to an extraordinary fecundation which acts 

 upon the seeds and modifies them at the moment 

 of their conception. 



ART. VIII. Phenomena observed in hybrid plants. 

 Observation /.There is a species of Citrus 

 known in Italy by the name of bizzaria, and in 

 France by that of the hermaphrodite orange 

 (aurantium limo titratum,fplio etfructo mixto), and 

 which bears at the same time sour oranges, lem- 

 ons, citrons, and mixed fruits. 



I have observed upon this hybrid that the same 

 branch bears at the same time" leaves and flowers, 

 of which some announce the sour orange tree, 

 others the lemon, and still others the citron tree. 

 They produce fruit which belong sometimes to 

 one of these species, at other times to two or 

 even three of them mixed. 



A scion which springs up violet often devel- 

 ops a branch, some of whose flowers are violet, 

 others white, and the buds of this branch grafted 

 upon another stock sometimes produce there the 

 caprices of the variety, and sometimes perpetu- 

 ate a simple sour orange, although they may 

 have been taken from the axil of a citron leaf; 

 and reciprocally a simple citron, though taken 

 from the axil of a sour orange leaf. 



This caprice has forced the gardeners to mul- 

 tiply it by the layer. It is thus that this hybrid 

 is perpetuated without degenerating. 



Observation II. I fecundated white pinks with 

 red pinks reciprocally The seeds thus produced 

 gave pinks of mixed flower. Several of these 

 plants presented the following phenomena : The 

 same plant which gave mixed flowers gave some 

 flowers entirely white, and others entirely red. 

 One .year it gave only red flowers, and the next 

 mixed flowers again. Others, after having pro- 

 duced mixed flowers two or three years, subse- 

 quently produced only red ones ; they seemed 

 entirely to have returned 1o the species. 



