Evolution. — Morphologie. 263 



Zabel, H., Zwei interessante Thymus-F ormen. (Mit- 

 theilungen der Deutschen Dendrologischen Gesellschaft. 1901. 

 p. 98—99.) 



1. Thymus Serpyllum V vulgaris, in zwei Exemplaren zwischen 

 T. vulgaris gefunden; keine Beschreibung. 2. T. Serpyllum f. Kerme- 

 s/n«s Zabel: Blumenkronen lebhaft karmoisinroth. 



Correns (Tübingen). 



Waisbecker, A., Die Variationen und Hybriden der 



Cirsium -Arten des Eisenburger Comitates in 



Ungarn. (Termdszetrajzi-füzetek. Bd. XXIV. p. 332— 344.) 



[In magyarischer Sprache.] 



Als neu werden beschrieben: Cirsium erisithales Scop. var. spinu- 

 losum Waisb. und Cirsium adulterinum Waisb. (= eine Form der Hybride 

 C. erisithales X Pannonicum). Matouschek (Reichenberg). 



Baker, F[rederick] H[arry], On the constancy of specific 

 characters of the genus Eucalyptus. (Rep. Australas. 

 Assoc. Sei. VIII. 1900 [1901]. p. 229—231.) 



A criticism of the species founded on morphological characters, 

 which, it is contended leads to error; vital characters should be taken 

 into account in framing species. B. Daydon Jackson. 



Hamilton. Alexander G., Some examples of alteration 

 produced in plants by changed environment. 

 (Rep. Australas. Assoc. sei. VIII. 1900 [1901]. p. 232—235. 

 Plates 5, 6.) 



The plants under review are Dendrobium aemulum and D. tetrn- 



gonum under different ecologic conditions. B. Daydon Jackson. 



Masters, Maxwell T[ylden], Hybrid Conifers: an address 

 to the Scientific Committee. (Reprinted from the 

 Journal of the Royal Horticultural Society. 8°. 25 cm. p. 14. 

 With figures. London [Spostiswoode <& Co.] 1901.) 



A summary is given of the existing knowledge of hybrid Conifers, 

 followed by a detailed description with figures of Abies Vilmorini X 

 raised between A. Pinsapo 9 ^nd A. cephalonica rj. 



B. Daydon Jackson. 



Leavitt, R. Gm Predetermined root-hair cells in 



Azolla and other plants. (Science. N. S. XIII. p. 



1030—1031. June 28. 1901.) 



In contrast with De Bary's statement that special hair 



cells can be distinguished from the other epidermal cells of the 



root only in Lycopodium, Mr. Leavitt reports them from 



Azolla, Isoetes, Selaginella, Equlsetum, certain Alismales and 



certain Nymphaeaceae. Attention is called to the fact that the 



last-named group agrees with monocotyledons and certain 



Pteridophytes in that the epiblema is not epidermal but con- 



sists of the outermost layer of cortex. Trelease. 



