756 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



"drained" and " undrained," but the plants of these are not always 

 clearly differentiated, and further explanations are required. Fifteen 

 plants characteristic of bogs across North America were considered. Of 

 these three only are endemic, the rest are in Europe and Asia ; hence they 

 are preglacial and circumpolar. A consideration of the probable glacial 

 conditions follows, and the paper concludes with a general summary, 

 epitomised as follows : — 



Colder North American bog societies are closely related to those of the 

 Old World. 



The climate is moist and subject to extremes. 



Passing north or south arborescent species are the first to disappear, 

 till only herbaceous species remain. 



The bog societies are normally related to the conifer forests, but where 

 surrounded by Oaks and Hickories they show no order of succession to the 

 forests. 



The present bog societies are continuations of early postglacial ones. 

 Bog societies are composed of boreal species. — G. H. 



Botanical Survey of the Huron River Valley. By L. H. Weld 



(Bot. Gaz. xxxvii. No. 1, p. 36). — This paper treats of " A Peat Bog and 

 Morainal Lake," with photos and diagrams showing sections of subsoils. 

 The lakes were formed in the moraine. A luxuriant flora probably 

 flourished in the terminal moraine on the retreat of the ice. It was 

 first invaded by aquatic and amphibious plants. As humus accumulated 

 sedges and sphagnum followed ; then shrubs, and finally a soft-wood 

 deciduous forest.— G. H. 



Brassica sinensis, the Pe-tsai (white vegetable). By J. 



Cure (Rev. Hort. pp. 342-844, July 16, 1904 ; 1 woodcut).— A description 

 of a vegetable cultivated very largely in China, a species of Cabbage, 

 which apparently might be introduced here to advantage as a winter 

 vegetable capable of improvement. — C. T. D. 



Broomrapes. By H. Garman (U.S.A. Exp. Stn. Kentucky, Bull. 

 105, March 1903 ; 15 figs.). — An account of the germination and para- 

 sitism of the Broomrape, Orobanche ramosa, on Hemp and other plants is 

 given, together with notes on some other species (0. ludoviciana, 0. minor, 

 Leptamnium virginianum, Thalcsia uniflora, and Conopholis americana), 

 and on remedial measures. Cleaning Hemp seed by machinery was the 

 best means ; neither soaking seeds of Hemp in copper sulphate solution 

 (lib. to 5 gallons) nor hot water (140° F.) applied for ten minutes proved 

 injurious to the Hemp seed, but prevented the Broomrape from ger- 

 minating ; while copper sulphate applied at the rate of 1 ton per acre, and 

 unslaked lime at 2*72 tons per acre, also had a beneficial effect. Iron 

 sulphate at the rate of 680 lb. per acre, and gas-lime at the rate of 5^ tons 

 per acre, did not affect the germination of the Broomrape seed, while 2 tons 

 of sail per acre prevented the germination of both Hemp and Broomrape. 

 A list of 29 plants attacked by Orobanche ramosa and 44 attacked by 

 O. minor is quoted from Koch's " Entwicklungsgeschichte der Oroban- 

 ehen."— F. J. C. 



