61 



I 



Stelzneriana, which nevertheless exhibited two dif- 

 ferent characters. Some individuals were in every 

 respect like those obtained in 1859, the under side 

 of the fronds being covered with golden dust, and 

 the young fronds slightly crested at their extremi- 

 ties ; whilst the others had narrower, more hairy 

 fronds of less size, and not so powdery. The most 

 singular part of the affair was that all the plants of 

 each character after less than a year's cultivation 

 yielded perfect spores, which on being sown repro- 

 duced the varieties, and their fronds are three times 

 the size of those of their parents. I also made ex- 

 periments with Gymnogramma gracilis, pulveru- 

 lenta, argjTophylla, L'Herminieri, and Laucheana, 

 sown indiscriminately together. 



The spores of Gymnogramma gracilis were those 

 of a plant which I had grown some ten years, when 

 that fern was quite new, and it was isolated not 

 merely from every other Gymnogramma, but also 

 from every other fern, for it was the only one in the 

 house ; the spores of the other species came from 

 plants which had never been in any way in contact 

 either with Gymnogramma gracilis or G. tartera. 

 The results were as follows . — 



Gymnogramma pulverulenta sulphurea. — Both 

 sorts of the fronds were covered with pale yellow 

 dust. I only obtained three plants, which I unfor- 

 tunately lost in winter. 



G. gracilis hybrida^ intermediate between G. gra- 

 cilis and G. lanata, and resembling G. tartera. Some 

 of the plants are densely covered with a briglit sil- 

 very dust, others with a yellowish white dust, and 

 in others again it is altogether wanting. All are 

 covered at the base of the fronds with a dense 

 brown down more or less deep in color. 



G. gracilis elegantissima, with very finely cut 

 fronds, densely covered on both sides, with a yel- 

 lowish-white powder. 



G. gracilis superba, the most ornamental and 

 valuable of all. The fronds, which curve very 

 gracefully, are not nearly so finely cut as in the pre- 

 ceding, but are broad, of a bright glossy green, 

 with a metallic lustre on the upper surface, and 

 covered beneath with a very thick coating of yel- 

 lowish-white powder. This is one of the hardiest 

 of all Gymnogrammas. 



G. hybrtda davallicefolia, the result of a fertili- 

 zation of G. L'Herminieri. Its merits consist in 

 the number and fineness of its pinnules, forcibly 

 reminding one of some graceful Davallia ; its fruc- 

 tification is also very ornamental. 



Gymnogrammas are readily crossed, but up to 

 the present time other genera have not produced 

 hybrids. I have, it is true, obtained some varia- 



tions of form, such as Davallia tenuifolia stricta, 

 a tufty variety of D. tenuifolia, and Pteris asperi- 

 caulis from the seeds of Pteris tricolor, which may, 

 perhaps, tend to prove that the latter is only a hy- 

 brid or variety of Pteris aspericaulis, and all the 

 more because it is absolutely the same as the latter 

 in its mode of growth. These forms remind one 

 of the hardy ferns, most of which are so interest- 

 ing and ornamental, and of which the spores always 

 reproduce the same forms, as I found some years 

 years ago by experiment on Athryrium Eilix-foe- 

 mina Frizellise, and again more recently in the case 

 of Osmunda regalis cristata. 



Did the last-mentioned forms also result from fe- 

 cundation ? I do not think so, because there are 

 plants, though comparatively few in number, which 

 return to the type after having preserved for a 

 whole year the character of a particular form of the 

 type. Experience has taught me, as it has many 

 others, that the pro-embryos can be preserved as 

 long as the plants themselves, and that they can be 

 divided and thus serve for propagation where the 

 number of plants obtained is small. All that is 

 necessary to be done is to cut off the young plants 

 with a very sharp knife, always taking care to pre- 1 

 serve the pro-embryos. It is more particularly to | 

 those of tree and other very large ferns that this | 

 mode of proceeding applies. My experiments have 

 likewise taught me that a high temperature has- 

 tens and is favorable to the germination of the 

 spores, and their hybridization. I always give a 

 sufficient degree of heat to kill every Phsenoga- 

 mous plant. 



As a nurseryman, my experiments have naturally 

 been limited, only extending to the most ornamental 

 species sought after in commerce ; and for the 

 same reason I could not afford the time and the 

 appliances necessary to attain a definite result, if 

 such were possible. It is the part of practical gar- 

 deners to perform horticultural labors with intelli- 

 gence, and to observe the facts and appearances 

 which serve to guide men of science in profound 

 and intricate investigations.. — A. Stelzner, {Bul- 

 letin de Congres International de Botariique et d' 

 Horticulture d' Amsterdam.) 



Renovating Sickly Grapes.— Muscat grapes 

 apparently beyond recovery, and in a border perma- 

 nently wet, were saved by a whole measure, con- 

 sisting in the making of a new border on the top 

 of the old one, and then planting on the new bor- 

 der Black Hamburghs to serve as healthy feeders 

 to the Muscats. "As soon as these got of sufficient 

 strength to admit of it," says Mr. Clarke, "they 



