Morphologie, Teratologie, Befruchtung, Cytologie. 611 



arranged in the soil, that as an average deepest situated were those 

 flowering and raising the bulb, then those raising the bulb but not 

 flowering; then follows those flowering but not raising the bulb, 

 and those not flowering and not raising the bulb had the highest 

 Situation. As to the size of the bulbs, flowering plants have the 

 thickest ones, and. what is more important, the size of the bulb 

 increases with the depth. The author thinks that the abnormal sizes 

 found are to be regarded as reactions upon abnormal depths, be- 

 cause the percentage of small bulbs raising is increasing much more 

 with the depth than the percentage of big ones raising. Thus, Ga- 

 lanthus seems to have no definite normal depth for its bulbs as a 

 whole, but there seem to be different normal depths for the diffe- 

 rent sizes of bulbs. Ove Paulsen. 



Boodle. L. A., On the trifoliolate and other leaves of 

 the Gorse {Ulex eiiropaeus, L.). (Ann. Bot. XXVIII. p. 527—530. 

 1914.) 



In seedlings of gorse, the axis usually bears a certain number 

 of trifoliate leaves, after the cotyledons and before the simple 

 leaves. The production of trifoliate leaves is to be regarded as an 

 ancestral character. As the result of an experiment, in the course 

 of which 2,895 seedlings were grown and examined, the author 

 concludes that seedlings of gorse grown on good soil produce a 

 somewhat larger average number of Compound leaves than those 

 grown on sand. The Suggestion is put forward that this is a case of 

 an ancestral character being favoured by ancestral soil conditions. 

 The author shows that this result harmonises with his previous 

 experimental work on the wallflower. (See Ann. Bot. XXII. p. 714). 



Agnes Arber (Cambridge). 



Harris, J. A., On a chemical peculiarity of the dimor- 

 phic anthers of Lager stroemia indica, with a Suggestion 

 as to its ecological significance. (Ann. Bot, XXVIII. p, 

 499—507. 2 textfigs. 1914.) 



In the Malayan shrub, Lagerstroemia indica, the stamens are 

 dimorphic, those of the outer whorl being larger than the more 

 central yellow group, and differing from them not only in colour, 

 but, as Darwin showed, in the poUen which they contain. The ob- 

 servations described in this paper show that the differentiation is 

 not merelj^ morphological, but that it is physiological as well. The 

 large (outer) anthers lose water much more rapidly by evaporation 

 than do the smaller ones. The underlying cause of the physiological 

 differentiation seems to be chemical rather than physical. A water- 

 soluble substance seems to occur only, or in greater abundance, 

 on the smaller anthers, w^hich lowers their rate of water loss. The 

 ecological consequence of the physiological differentiation is that the 

 pollen of the larger anthers furnishes booty to the visiting insects 

 in a form which does not require moistening for transportation, 

 while the outer whorl of anthers, which are inconspicuous because 

 isochromatic with the coroUa, supplies dry powdery pollen, which 

 is scattered over the body of the visitor and serves for fertilisation. 



Agnes Arber (Cambridge). 



Rogers, R. S., Mechanism of pollination in certain 



