Floristik, Geographie, Systematik etc. 285 



Sonchus- Arter. [Some Remarks onourannualSpeciesof 

 Sonchus]. (Bot. Tidsskr. XXXIV. p. 343—346. 1917.) 



The author has got seeds of Sonchus oleraceus L. from many 

 different places and has grown them in the Botanical Gardens of 

 Copenhagen. From his investigations it appears that plants of 

 different origin (Denmark, England, Scotland, Ireland, Italy, 

 Turkey, West-Indies, West-Australia and several botanical 

 gardens) resemble each other very much. But nevertheless there 

 are small differences which show that we have to do with a col- 

 lective species. These differences are found as regards the leaves, 

 the color of the coroUa, the presence or absence of glandulär hairs 

 on the Upper part of the stem and the peduncles and on the invo- 

 lucral leaves, and they may be combined in different ways; thus 

 an exhaustive analysis would be a very troublesome task. From 

 the different shape of the leaves we may distinguish the common 

 form as var. triangularis Wallr., a rare form as var. lacerus {^iWd.) 

 Wallr. (grown from seeds collected near Queenstown, Ireland, 

 and Lizard, Cornwall). A white-flowered form is var. albescens 

 Neum. which is found both in var. triangularis and in var. lacerus. 

 Intermediates (hybrids) between these forms are common. 



As to the other annual species 5. asper (L.) Hill, it has two 

 much different forms according to the leaves, viz: «, inermis Bischoff 

 and ß, pungens Bischoff, which both breed true. 



The many species of this group described from tropical coun- 

 tries in earlier times are all to be included under the two here 

 mentioned collective species and have no doubt come to the Tro- 

 pics with the colonists. C. H. Ostenfeld. 



Ostenfeld, C. H., Skildringer afVest-Australiens Natur, 

 saerligt dets Plan tevaekst. [Descriptio ns of the Nature 

 of West-Australia, especially of its Plant life]. (Geogr. 

 Tidskr. XXIII. p. 35—46, 132—148. 30 figs. Photos and maps. K0- 

 benhavn, 1915.) 



A populär description of the geography and Vegetation of West 

 Australia based upon a visit paid by the author in 1914.) 



As to the Vegetation of the State three regions are admitted: 

 1. The tropical West-Australia: savanne forest characte- 

 rized a. o. by Adansonia Gregorii, Gyrocarpus , Eucalypti etc.; savan- 

 nes: mangroves with Avicennia and Rhisophora's, etc. 2. Thelnte- 

 rior and the north-westerncorner ofthe State {Eremaea): 

 Mulga scrub with Acacia^s etc.; Eremaean Eucalyptus forest wit hjE. 

 sahnonophloria etc.; dune formation; salsolaceous coastal formation, 

 etc. 3. The south-western part ofthecountry: rieh forest 

 Vegetation of many belts characterized by different Eucalypti, as 

 adrnirably described by L. Diels in 1906, The most luxuriant belt 

 is that in which the giant Karri {Eucalyptus diversicolor) dominates; 

 it requires a high annual rainfall. C. H. Ostenfeld. 



Petersen, O. G., Traeer og Buske. Diagnoser til dansk 

 Frilands-Traevaekst. [Trees and shrubs. Diagnoses of 

 Danish open land trees]. (1517 pp. 248 figs. Kobenhavn oz 

 Kristiania, 1916.) 



The book contains more than 1500 descriptions of trees and 



