NOTES AND ABSTRACTS. 



785 



generation. The doubles have no functional gynfficeuni and yield no 

 seed, but the stamens are functional. There is some evidence that more 

 than one factor is concerned in determining the occurrence of singles 

 and doubles.— J. G, 



Draba ciliata. By J. Wood {Garden, June 4, 1910, p. 275).— 

 This plant is considered worthy of notice and an acquisition to the rock 

 garden. The flowers are white and the leaves form a dense cushion of 

 green, the plant attaining a height of five to six inches. It is of 

 easy growth and does not share with other Drabas the bad habit of 

 dying off in places when two or three years old. D. ciliata is the most 

 profuse flowering species and equally at home in the ordinary rock 

 garden or on a dry w nll, not being particular whether it is planted on a 

 slope or on level ground. It would do for the edge of a border near 

 the path, in company with mossy Saxifrages. — H. R. D, 



Echevepia, Three New S. American Species of; (Jour. Soc. Nat. 



Hort. Fr. ser. iv. vol. xi. p. 204; April 1910). — Dr. Purpus, of the 

 Botanical Gardens at Darmstadt, who spent the best part of the years 

 1907 and 1908 botanizing among the mountains of Puebla, particularly 

 near Saint Louis Tultitlanapa and on the top of Orizaba, collected many 

 new succulents in those regions. Of these, three new Echeverias — 

 E. gigaiitea, E. setosa, and E. suhalpina — are interesting to horticul- 

 turists, particularly the last, which forms rosettes 20 to 25 centimetres 

 in diameter, the corolla being reddish-purple 12 millimetres wide with a 

 yellowish centre, the petals being bordered with yellow. — M. L. H. 



Elm Seedlingrs showing Mendelian Results. By Augustine 



Henry, M.A., F.L.S. (Jour. Linn. Soc. xxxix. 1910, pp. 290-300; 

 5 plates and 2 text figs.). — There are two species of elms in the British 

 Isles — Ulmus montana With., and Ulmus glabra Miller. In addition 

 to these two species there are many so-called varieties of elms, some 

 of which are considered to be varieties of U. glabra, others being sup- 

 posed to be distinct species. The most remarkable of these is the 

 " English Elm," Ulmus ca7npestris of English botanists. The author 

 is of the opinion that this, like the other varieties of elm in England, 

 is one of the descendants of the first cross between the two species, 

 ' possibly due to a second hybridization of some of these descendants 

 with U. fnontana. 



The Huntingdon elm (U. vegeta) is most probably a first cross 

 between U, glabra and U. montana. It is like most first crosses, extra- 

 ordinarily vigorous, growing faster than any other elm. The Hunting- 

 don elm originated as a seedling in a nursery at Huntingdon about 

 1746-56. Most of the characters of U. glabra are dominant in it. 

 A great many other kinds of elms are known which vary in habit and 

 fohage. 



In June 1909 the author made extensive sowings of elm seeds. 

 The first fact which he found was that only two kinds of elms give, 

 VOL. xxxvi. 3 F 



