542 JOURNAL OF THE EOYAL HORTICULTURAL SOCIETY. 



till the middle of January, then forced on, and moderately watered. It 

 should be a mass of bloom by March 15, the boughs having been trained 

 in the form of a pyramid.—^ 7 . A. W. 



Gymnosperms, Evolutionary Tendencies (Bot. Gaz. vol. xlviii., 



No. 2, pp. 81-97, August 1909). — In this paper, Professor John M. Coulter 

 traces the general history of the Gymnosperms. In the Palaeozic period 

 the two groups Cordaitales and Cycadofilicales (sic) were already 

 separated. From the latter sprang the Bennettitales and Cycadales of the 

 Mesozoic. The Ginkgoales and Coniferales are supposed to have originated 

 in the Cordaitales. Of Coniferales, Abietineae and Araucarineae were the 

 first to appear. Taxodineae, Cupressineae and perhaps Taxineae are traced 

 to the primitive Abietineae, and Podocarpineae are derived from Arau- 

 carineae. Gnetales may possibly have sprung from the primitive 

 Cupressineae. 



The author then discusses the phytogenetic changes in vascular 

 anatomy, leaf, strobilus, stamen, ovule, embryo, and female and male 

 gametophyte. — G. F. S.-E. 



Helianthus sparsifolius. By S. Mottet (Le Jard., vol. xxiii. 

 No. 538, p. 217 ; July 20, 1909 ; 2 figs.).— This Helianthus was intro- 

 duced to the Natl. Hort. Soc. of France in 1906. It is an American 



hybrid, obtained from Helianthus rigidus x H. annuus var. calif omicus. 

 It is a valuable border plant, but is unfortunately sterile and needs 

 protection in winter. It resembles H. laetiflorus rather than H. rigidus, 

 but is infinitely superior to the well-known variety of the former, £ Miss 

 Mellish.' The plant attains a height of 3-4 m., the flowers being 

 extremely abundant and lasting till the end of September. The capitula 

 are 15-18 cm. in diameter, with a good disc, and four rows of ray florets, 

 which roll slightly inwards.— F. A. W. 



Hollyhocks.— By M. Alin (Le Jard., vol. xxiii. No. 537, p. 200; 

 July 5, 1909 ; coloured plate). — In the general observations in this 

 article the author comments on the curious fact that double Hollyhocks 

 are fertile, since only the filaments of their stamens are transformed into 

 petals. The anthers persist and are very productive. Accordingly the 

 plant is almost always raised from seed. Some growers, however, prefer 

 to divide the clump, or to graft, or take cuttings, to ensure the purity 

 of any special strain. Directions for all these methods are given in the 

 article, and are familiar to English gardeners. Hollyhock disease (due to 

 Pucci?iia malvacearum) may be checked by setting the plants sufficiently 

 far apart and not growing them too long in the same spot. It is also 

 advisable to sponge the leaves on both surfaces, with a TT foo solution of 

 copper sulphate. — F. A. W. 



Hybridization of Peas. By F. Wakerley, M.Sc. (Gard, Mag. 

 No. 2891, March 27, 1909, pp. 244; figs.).— Results of hybridization of 

 edible peas compiled from experiments conducted at the Midland 

 Agricultural and Dairy College. The effects of a large number of crosses 

 are recorded and well illustrated by a series of figures. — E. B. 



