Anatomie. — Varietäten, Descendenz, Hybriden. 67 



Schlüssel, bei der Gattung mitunter auch ein solcher. Bei den Arten 

 findet man eine genaue Beschreibung des Blattes, der Epidermis- 

 und Pallisaden-, ferner der Kristallsandzellen, die Literatur und 

 Verwendung der Pflanzenart angegeben. — Uns interessieren na- 

 mentlich folgende Daten: 



1. Bei Cerinthe: Die C3^stolithischen Inhaltskörper sind im Ge- 

 gensatze zu jenen der anderen Borragüieen-Gsutungen dadurch auf- 

 fallend, dass die Kalkeinlagerungen kristallinischer Natur sind. 



2. Bei Scopolia wurden Drüsenhaare gefunden. 



3. Im Gegensatze zu Fedde beobachtete Verf. Kristallsandzellen 

 bei Solanum auch in der Palisadenschicht (z. B. bei S. dulcamara, 

 S. Melongena, doch auch bei Lycium barbarum). 



4. Solanum ist nach morphologischen Merkmalen nur schwierig 

 in Gruppen zu zerlegen. Die Arten mit Stern- und Schildhaaren, 

 dann die mit reh- oder hirschgeweihartigen Haaren bieten ähnliche 

 Handhaben zur Gruppenbildung wie bei Rubus- und Potentilla. 



5. Bei Coffea arabica fand Verf. Kn r pten , die bisher bei dieser 

 Gattung unbekannt waren. Matouschek (Wien). 



Ostenfeld, C. H., Further Studies on the Apogamy and 

 Hy bridization of the Hiemcia. Zeitsch. f. indukt. Abstamm. u. 

 Vererbungslehre. III. 4. p. 241 — 285, with 1 coloured plate. 1910.; 



The author reports on his continued experiments in the apogamy 

 and hybridization of the Hieracia. 



Apogamy. The only two hitherto examined species of the sub- 

 genus Sle)iotheca require normal fertilisation in order to produce 

 seeds capable of germinating. In the subgenus Archieracium by far 

 the most of the numerous species examined are absolutely apogamic. 

 By means of counting the numbers of fully developed seeds in 

 „castrated" and "not castrated" heads the author arrives at this 

 result, that the proportion is, broadly spoken, the same in both cases. 

 Some few of the examined apogamic species deviate from this rule, 

 as it seems that some of the flowers in the heads require fertilisa- 

 tion in order to develop seeds. Among the Achieracia one species 

 Hieracium vivga aurea is not apogamic, and another, ff. umbellatum, 

 behaves in the same manner with the exception of one Single race. 

 In the suboenus Pilosella some species are apogamic, others not, 

 and the apogamic ones are not absolutely apogamic, as shown by 

 counting the numbers of developed seeds in the same manner as 

 mentioned above. 



H y bridization. In one group of species hybrids (ff. pilosella 

 X aurantiacum, ff. auricula X nurantiacum (partly) and ff. excel- 

 le>/s X pilosella) the F r generation is self-sterile. By crossing the F 1 

 with one of the parcuts, an F 2 of few individuals has been obtained 

 which seems to segregrate. In another group F T is rather fertile by 

 isolation and F 2 and F., show füll constancy [ff. excellens X auran- 

 tiacum, and partly ff. auricula aurantiacum), thus an experi- 

 mental proof is given that by hybridization between far distant 

 species within the subgenus Pilosella new forms can arise which 

 are fully constant and which behave as new species. 



The peculiarity in Hieracium that the F r individuals of the same 

 cross are heterogeneous, found by Mendel, is reproofed. 



Apogamy and its relation to poly morphism. From the 

 experiments and from the literature concerning this subject the 

 author concludes, that there is an evident relation of apogamy to 



