102 SAXIFRAGES. [Saxifraga. 
seedlings of each plant were raised. The 45 seedlings of 
8S. Geum matured into plants with rounded petioles like their 
parent. A few of them differed either by the absence of the 
leaf sinus or by a slight flattening of the marginal teeth. 
Both these divergences appear to indicate that the plant 
selected as parent was not itself quite pure. Of the self- 
pollinated S. umbrosa seedlings, 43 had leaves and petioles 
like their parent, the remaining 2 had nearly circular leaves 
tapering into rather rounded petioles ; here again traces of 
mixed origin in the parent were shown. 
For the hybridisation experiments, individuals of the 
selfed-generation of both S. Gewm and S. umbrosa were 
selected identical in leaf-form with the original parents ; 
cross-pollination of these was effected and seeds were pro- 
duced. These seeds grew into plants of which some leaf- 
outlines are shown on PI. IV., figs. 5-16. Continuing the 
experiments, the hybrid plant represented by fig. 5 on this 
plate was then self-fertilised, some of the resulting forms 
being shown in figs. 17, 18. A similar treatment of the 
hybrid plant fig. 7, gave the forms 19-21. As will be seen, 
these experiments resulted in the production, amongst other 
forms, of plants which fully comply with the Linnean 
definition of S. hirsuta ‘‘ foliis cordato-ovalibus,”’ and thus 
demonstrate that this Linnean species has its origin in the 
hybridising of S. Gewm with S. umbrosa. Some of the forms 
so produced along with S. hirsuta may be matched with 
leaves gathered from natural plants and shown on Plates 
I. II. WI. & VI. 
In these experiments the hermaphrodite S. Geum and S. 
umbrosa were used indifferently as the pollen- or seed- 
parent. 
2. ANALYSIS OF 8. HIRSUTA. 
Having thus proved that S. hirsuta can be produced by 
the union of 8. Geum with S. umbrosa, it remains to be 
shown that the parents can be produced by the analysis of 
S. hirsuta—a reversal of the synthetic process already 
described. Two plants of Linnéd’s S. hirsuta, gathered near 
the base of Tore Mountain, Killarney, were received into 
cultivation at the College Botanic garden and self-pollinated 
there. Leaf-outlines of the selected plants are shown on 
Pl. V.,* figs. 22 & 23. Thirty seedlings of each plant were 
* PLATE xs (3 life-size)—Hybridising Experiments, Analysis of S. hirsuta 
inn, 
Leaves from plants selected for experiment, figs, 22, 23, 
Leaves from resulting plants, figs, 24-36, 
