182 Biologie. — Morphologie etc. — Varietäten etc. 



Allgemein zieht Verf. aus seinen Beobachtungen den Schluss, 

 dass die Form der Windblätter eine Funktion der Bewegungsform 

 ist. Die Blattgestalt wird durch den Wind hervorgerufen und 

 schützt zugleich gegen den Wind. 



Zum Schluss berichtet Verf. über Versuche mit einem System 

 von drei Kapillarröhrchen. von welchen das eine nach vorn, die 

 anderen nach je einer Seite gerichtet waren. In dieses System 

 wurde Wasser durch ein grösseres Rohr hineingedrückt. Bei ver- 

 schiedenen Bewegungen des Systems wirkte die Zentrifugalkraft 

 auf die Strömung in den verschiedenen Röhren in derselben Weise, 

 die nach der Vermutung des Verf. für die durch den Wind herbei- 

 geführte Strömung in den Blättern massgebend ist. 



Grevillius (Kempen a. Rh.). 



Conipton, R. H., Xerophily in the Coniferae and Micro - 

 phylly. (New Phyt. X. p. 100-105. 1911.) 



The highly controversial literature on the subject of the con- 

 nection between the xerophily of the Conifers and their ecological 

 relations, is quoted and discussed. The author's own view is that 

 the Conifers are rigidly microphyllous forms, that the power of 

 freely adapting themselves to ecological conditions is strictly limited 

 by the lack of plasticity in leaf structure. It is suggested that the 

 lack of ability of this foliar vascular System to branch with ease 

 is one of the causes which have contributed to keeping the leaf 

 small. Given this cramped, hereditary type of structure, ecological 

 adaptation appears to have been the result of two processes going 

 on simultaneously: 1) the development of enormous numbers of the 

 rigidly constructed leaves with a view to increased assimilation 

 and growth, and 2) the production of xerophily in the individual 

 leaves as a compensation for the resulting increase of surface . 



Agnes Arber (Cambridge, England). 



Bateson, W. and R. C. Punnett. On the Inter-relations of 



Genetic Factors. (Proc. Roy. Soc. London, B. LXXXIV. p. 



3—8, 1911.) 

 de Vilmorin, P. and W. Bateson. A Case ofGametic Coup- 



ling in Pisum. (Proc. Roy. Soc. London, B. LXXXIV. p. 9—11, 



1911.) 

 Gregory, R. P., On Gametic Coupling and Repulsion in 



Primula sinensis. (Proc. Roy. Soc. London, B. LXXXIV. p.,12 — 



15, 1911.) 



In the flrst of these three papers Bateson and Punnett give a 

 review of the position gained at the time of writing in the investi- 

 gation of the special inter-relationships which have been found to 

 occur in some cases between distinct genetic factors. The second 

 and third papers describe cases in which phenomena of this kind 

 occur. 



Early in the investigation of heredity in the Sweet Pea (Lathy- 

 rus odoratus), it was observed that in plants heterozygous for two 

 distinct factors the distribution of these factors was in certain cases 

 disturbed in definite ways, such that particular combinations of fac- 

 tors occurred in the gametes with greater frequency than the rest. 



The phenomena exhibited in these cases led to the recognition 

 of: — 



