Morphologie etc. — Varietäten, Descendenz, Hybriden. 275 



developpement and significance of the longitudinal fission in the 

 spireme ribbon, the method of origin and grouping of the chromo- 

 somes on the prophases, and the origin and subsequent fate of the 

 nucleoli. The results may be summarised as follows: 



At the end of the prophase the chromosomes are arranged in 

 eight^ pairs on the equatorial plate and the members of each pair 

 roughly correspond with one another in form. During the anaphase 

 the fission which will effect the Separation of the daughter chromo- 

 somes at the subsequent division is marked out A chromatin knot 

 is formed by the fusion of parts of chromosomes and gives rise to 

 the nucleolus. During the prophase the nucleolus gives up its 

 chromatin to the developing spireme. When the spireme is formed 

 it is longitudinally split and appears to be continuous. Later it 

 Segments into 8 chromosomes, which finally segment into 16, 

 which are arranged in 8 pairs. No evidence was found in favour 

 of the theory that the sudden collapse of the nuclear vacuole is 

 responsible for the appearance of the achromatic spindle. It was 

 not found possible to demonstrate the presence of a distinct nuclear 

 membrane. The gametophytic nuclei, like the somatic, show the 

 double type of spireme. Agnes Arber (Cambridge'. 



Welsfopd, E. J., The Genesis of the male nuclei in Liliiim. 

 (Ann. Bot. XXVIII. p. 265—270. 2 pl. 1914.) 



The present paper forms a continuation of the memoir on the 

 fertilisation in Lilhan auyatum and L. tnartag07i published b}^ the 

 author and Prof. Blackman (Ann. Bot. XXVII. p. 3, 1913). The 

 Chief results obtained are as follows: 



The vermiform nuclei of Lilium auraturn and L. Mavtagon pass 

 down the pollen tube in male cells and are usually only liberated 

 from their cytoplasm after the pollen tube has entered the embryo 

 sac. The male nuclei are regarded as possessing motility from an 

 early stage of their development. The „X-Körper" of Nawaschin 

 are shown to be the disintegrating cytoplasm of the male cell. The 

 history of the bands of granules sometimes found near the disinte- 

 grating cytoplasm suggests the possibility that they may be vesti- 

 ges of blepharoplasts. Agnes Arber (Cambridge). 



Lindman, CA. M., On Sagina procumbens L. X saginoides L. 

 Dalla Torre. (Bot. Notiser. p. 267—280. 4 Textfig. 1913.) 



Während der internationalen pflanzengeographischen Exkursion 

 nach den britischen Inseln im Jahre 1911 wurde auf Ben Lawers 

 in 'Schottland eine Sagina angetroffen, die später von Druce als 

 S. scotica n. sp., von Ostenfeld als S. procumbens X saginoides 

 beschrieben wurde. 



Diese Pflanze kommt nach Verf. auch in Skandinavien und 

 anderen europaischen Landern, sowie in Asien und Grönland 

 vor und ist, ähnlich wie S. saginoides, auf alpine und arktische 

 Gegenden beschränkt. 



Zuerst wurde dieser Bastard von Brügger im J. 1868 aus der 

 Schweiz mit der Bezeichnung S. media publiziert. Lagerheim 

 beschrieb ihn ausführlich aus Tromsö unter den Namen 5. Nor- 

 maniana. 



