Morphologie etc. — Varietäten etc. 195 



Knight, M., The Creeping Rootstock of Agropyrtmt repens. 

 (Journ. Bot. LI. p. 341-343. 1 pl. Dec. 1913.) 



The author describes the morphology and anatomy of the 'boring 

 apparatus' of the branches of the rootstock, and gives some details ot 

 the anatomy of the stem, leaf and root. The leaves covering the Un- 

 derground stem-apices possess bands of sclerenchyma converging 

 to the tip and forming a Sharp sclerotic point, and are armed with 

 stout recurved hairs. E. de Fraine. 



Mottier, D. M., Mitosis in the Pollen mother cells of Acer 

 negundo L. and Staphylea trifolia L. (Ann. Bot. XXVIII. p. 115 — 

 133. 2 pl. 1914.) 



The results obtained by Professor Mottier in the present in- 

 vestigation on the pollen mother-cells of Acer negundo differ widely 

 from those ofChesterA. Darling who has examined the same 

 species. Staphylea and Acer belong to closely related Orders. The 

 main results may be briefl}'^ summarised as foUows: 



Before synapsis no chromatin spireme is present. Synapsis is a 

 normal phenomenon and a real contraction occurs. No support is 

 found for Lawson's doctrine that synapsis is brought about merel)'" 

 by an enlargement of the cavity of the nucleus. In the spireme the 

 somatic chromosomes are united end to end, and where, at a 

 laier stage, the two members or halves of bivalents are seen l5''ing 

 side b}'- side this is merely due to subsequent approximation. It is 

 shown that chromosomes do not bud off bodily from the nucleolus 

 as described by Darling. The number of bivalents is probably 12 

 in Acer negundo, and 36 in Staphylea trifolia. 



Agnes Arber (Cambridge). 



White, O. E., A New Cytological Staining Method. (Science. 

 XXXIX. p. 394-396. 1914.) 



The author's objection to Flemming's safranin, gentian violet, 

 orange combination, and also to Haidenhain's iron alum, haema- 

 toxyUn method, is that they are not sufficiently translucent Avhen 

 dealing with nuclei which have a large number of chromosomes. 

 The difficulty was overcome b}'- the following method: Equal parts 

 of safranin Q in 50 per cent alcohol and a saturated Solution of 

 safranin in 3 percent Solution of anilin in water, are mixed, and an 

 equal volume of Magdala red in 90 per cent alcohol is added. 

 After filtering, this Solution is used as the red stain. A saturated 

 Solution of azure II is used as a contrast. The red stain is allowed 

 to act for several hours and the blue, only a few seconds. 



Charles J.' Chamberlain (Chicago). 



Fröhlich, A., Ueber den Bastard Roripa austriaca X sylvestris 

 und dessen Vorkommen in Mähren. (Oesterr. botan. Zeitschr. 

 LXIV. 3/4. p. 120-134. 8«. 1914.) 



Verf. beobachtete in der Umgebung von Kremsier in Mähren 

 Roripa-F orraen, die sich zwischen R. silvestris und R. austriaca 

 einschalten, sowie solche, die sich zwischen R. silvestris und R. 

 amphibia einschalten. Die Vielgestaltigkeit der erstgenannten Zwi- 

 schenformen, die an Ackerränden und ähnlichen trockenen Stand- 

 orten wachsen, erhellt aus einer Tabelle, in welcher 12 verschiedene 



