82 Anatomie. — Biologie. 



cies. In the smailer branches the stele exhibits a comparatively 

 simple structure closely resembling that in the seedling 



D. J. Gwynne-Vaughan. 



Thomas, Ethel N., Some Points in the Anatomy oiAcro- 

 stichiim aiireiim. (New Phytologist. Vol. IV. No. 8. p. 175. 

 1905.) 



A special interest is attached to this plant on account of 

 it being the only Vascular Cryptogam now known that lives 

 in salt-swamps. This investigation refers particularly to the 

 adaptations related to its habitat with the view of comparing 

 them with those of the fossil Vascular Cryptogams which pro- 

 bably had a similar mode of life In this light the discovery 

 that the middle cortex of the root of A. aiireiim is provided 

 with huge lacunae is of peculiar interest on account of the 

 presence of a similar zone in the roots of the Calamites. Psar- 

 roniiis etc. Further, the stele of the root contains a great cen- 

 tral mass of parenchymatous xylem with nine protoxylems; 

 six of which are in pairs alternating with the remaining three. 

 A comparison is drawn between the somewhat stem-like cha- 

 racter of these roots and the same feature that occurs in the 

 air-storing roots of the mangroves. 



The vascular System of the stem is a solenostele with a 

 few internal accessory Strands which come into relation with 

 the adapical margin of the stele at each leaf-gap. 



The vascular System of the petiole consists of a large number 

 of separate Strands apparently arranged in three more or less 

 incomplete circles. But from the manner in which the leaf- 

 traces depart from the solenostele of the stem, and from com- 

 parison with the early leaves of the young plant the author is 

 able to shew that the whole System is really only a very com- 

 plicated modification of the horse-shoe plan. The lamina shews 

 certain xerophilous characters in relation to the percentage of 

 salt in the water in which it lives. D. J. Gwynne-Vaughan. 



Harris, J. A., The dehiscence of anthers by apical 

 pores. (Report Missouri Bot. Gard. 16. p. 167— 257. 1905.) 



The author arranges the species showing apical dehiscence 

 in seven classes. It is shown that the mode of dehiscence is 

 characteristic of species, genera, and families very widely dis- 

 tributed taxonomically and also geographically. The conciusion 

 is reached that apical dehiscence is related to pollination by 

 various bees, especially by those which are active in the collec- 

 tion of pollen, and statistics are offered to show that the geo- 

 graphical ränge of these insects is similar to that of the plants 

 having the peculiarity in question, viz., there is a massing in 

 tropica! America, Australia, and the Indian regio n. 



M. A. Chrysler. 



