324 Anatomie. — Biologie. 



Kirk and Cockayne. The plants are all typical sub-antarctic xero- 

 phytes and include species oi Ranuncidus, Ligusticiini , Coprosma , 

 Cotula and other Compositae, etc. W. G. Smith (Leeds). 



Holm, Theo, Ceanothus Antericamts L. and ovatus Desf.; a mor- 

 phological and anatomical study. (Am. Journ. of Sc. XXII. 

 p. 523—530. f. 1—5. Dec. 1906.) 



The seedlings of C. Aniericanus and ovatus agree with that of 

 Rhammts catharticus, described by Irmisch; the cotyledons are 

 epigeic and subtend buds. In Ceanothus the first two leaves succeeding 

 the cotyledons are opposite in contrast to the others, which are 

 arranged in spirals. The primary root is long and slender with some 

 of the lateral branches transformed into mycorhizae. The primär}^ 

 axis above the cotyledons dies off at the end of the first season, 

 while the cotyledonary buds stay active, and grow out into two 

 vegetative shoots during the following season; the aerial shoot of 

 these species of Ceanothus do not last for more than one season, 

 but become replaced by the development of buds in the axils of, 

 the lowermost leaves of these shoots. Very characteristic is the 

 structure of the primarj^ root. In the second season the upper part 

 of the primary root has become compressed, and the internal struc- 

 ture shows that the rays of the hadrome have increased in thickness 

 much more on the one side of the root than on the other. A similar 

 case of excentric growth in the primär}^ root has been recorded by 

 Wigand, who observed such case in Ononis repens and spinosa 

 (Flora 185b. p. 674). 



The flowering stage is reached when the plant is about five 

 years old, and the flowers develop exclusively upon shoots of the 

 same season. In C. Aniericanus the infiorescences are constantly 

 lateral, the apex of each shoot being purely vegetative; while iii 

 C. ovatus the terminal as well as the lateral shoots are able to 

 develop flowers. 



The anatomy of the root shows the presence of sclerotic cells in 

 small groups, located in the secondary cortex, and the excentric 

 growth is very conspicuous in old roots. In the cotyledons the stomata 

 are distributed over both faces while in the succeeding leaves the)^ 

 are confined to the dorsal face in C. Ainericanus , but not in the 

 other species, in C. ovatus there are stomata on both faces of the 

 blade, but they are most numerous, however, on the dorsal. 



The stem shows a continuous ring of stereome inside the endo- 

 dermis surrounding the stele of collateral mestome-strands. 



When compared with each other these two species resemble 

 each other very much from seedling to mature plant. But characteristic 

 of C. ovatus is, however, the terminal infiorescences and the narrower 

 leaves with stomata on both faces. Theo Holm. 



Dennert, E., Biologische Notizen. Ein Hilfs buch für bota- 

 nische Selbstbeobachtungen auf Spaziergängen und 

 Excursionen. (Leipzig. Scheffer. kl. 8^. 178 pp. 1906.) 



Alphabetische Aufzählung unserer wichtigsten Pflanzen mit ganz 

 kurzen schlagwort-artigen Hinweisen auf die oekologischen Eigen- 

 tümlichkeiten einer jeden von ihnen. Die Arbeit ist in erster Linie 



