Bd. XCIII. No. 4. XXtV. Jahrgang. 



Botanisches Centralblatt. 



Referirendes Organ 



der 



Association Internationale des ßotanistes 



für das Gesammtgebiet der Botanik. 



Herausgegeben unter der Leitung 

 des Präsidenten: des Vice-Präsidenten : des Secretärs : 



Prof. Dr. K. Goebel. Prof. Dr. F. 0. Bower. Dr. J. P. Lotsy. 



und der Redactions-Commissions-Mitglieder: 



Prof. Dr. Ch. Flahault und Dr. Wm. Trelease. 



von zahlreichen Specialredacteuren in den verschiedenen Ländern. 

 Dr. J. P. Lotsy, Chefredacteur. 



Y -}A I Abonnement für das halbe Jabr 14 Mark 



* I durch alle Buchhandlungen und Postanstalten. 



1903. 



Alle für die Redaction bestimmten Sendungen sind zu richten an Herrn 

 Dr. J. P. LOTSV, Chefredacteur, Leiden (Holland), Oude Rijn 33 a. 



Raunkiaer, C, Kimdannelse uden Befrugtning hos 

 Molkebötte (Taraxacum). [Parthenogenesis in the 

 Ddind^Won (Taraxaciim).] [Danish.] (K^benhavn, Botanisk 

 Tidsskrift. Vol. XXV. 1903. p. 109—140.) 



As this important paper is vvritten in Danish, it seems 

 worth while to give here a detailed abstract of it. 



1. The author has found by cultivation that there are in 

 Denmark Sdistinct species of Dandelion, viz. Taraxa- 

 cum vulgare (Lam.), T. intermedium Raunk. n. sp., T. Ostenfeldü 

 Raunk. n. sp., T. speciosum Raunk. n. sp., T. Gelertii Raunk. 

 n. sp., T. erytlirospermum Andrz., T. decipiens Raunk. n. sp. 

 and T. paludosum (Scop.). The characters are taken from the 

 shape and direction of the involucral leaves and from the 

 anthers containing pollen or not. 



2. With regard tothedistribution and the conditionsfor 

 growth he has found the following rules: T. vulgare which is by far 

 the most common, grows everywhere, but principally in cultivated fields; 

 T. Ostenfeldü also prefers cultivated fields and moderately moist meadows, 

 Surther sunny places in woods ; T. Gelertii is to be found mostly in 

 woods, but also in meadows and low-lying fields; T. intermedium grows 

 in great abundance in peaty meadows; T. paludosum is confined to 

 marshy-meadows, and T. erythrospermum to dry and sandy localities; 

 the rare T. speciosum has been found in sunny, luxuriant fields; lastly 

 T. decipiens has been found only once. 



The author has established these conditions by numerous countings 

 of plants from different localities; he has examined 14000 specimens. 



3. The number of inner involucral bracts has been counted 

 in numerous specimens with the result, that T. erythrospermum and T. 

 paludosum have a distinct climax at 13^ while T. vulgare and T. Ostcn- 



Botan. Centralbl. Bd. XCIII. 1903 6 



