208 THE PI.ANT WORI.D 



with six to ten petals, and numerous short stamens of the same color as 

 the petals, and in the center of which are three small green carpels. The 

 leaves are ternatisect, of soft texture, a foot or more in length and about 

 the same in breadth, and more or less glaucous both above and below. 

 For the introduction of this lovely plant into European gardens we are 

 indebted to the Abbe Delavay, who discovered it in the mountains of 

 Yunnan, S. China, in 1882, and who sent seeds home to the Jardin des 

 Plantes. Part of the young stock came into the hands of Lemoine, of 

 Nancy, who worked up a stock and introduced it to commerce. From an 

 account of this plant which appeared recently in an American paper, it is 

 stated to graft readily on the roots of the herbaceous peony. I have not 

 tried this method, but have several times endeavored to work it on to 

 those of P. Moidan, but without success. It will no doubt prove to be a 

 useful plant to the hybridist on account of its color, and may be the pro- 

 genitor of a new race of peonies. In the note which accompanies the 

 figure in the Botanical Magazine mention is made of the interesting fact 

 that double and single forms occur in both the wild and cultivated state. 

 The Kew specimen has so far only produced single flowers. 



Our Teachers' Department. 



Edited by Professor Francis E. Eloyd. 



Teachers College, Columbia University, New York City. 



The editor of this department is at the present writing enjoying the 

 privileges offered by the Desert Botanical Laboratory of the Carnegie 

 Institution, at Tucson, Arizona. The object of the Laboratory is to make 

 it possible for the student of desert plants to get at the living material in 

 the field, but with the facilities at hand which are necessary for work ; and 

 this object is amply fulfilled. 



The building is situated on the side of a hill of volcanic rock, formerly 

 used by the Prapago Indians as a " trinjera," or fortress, to which they 

 retired from the attacks of the Apaches. Evidences of such occupation 

 are plentiful as one approaches the summit of the hill. The surface is 

 very stony, with occasional outcrops of the solid rock. There are also 

 a goodly number of pictographs to be found on the smoother rock faces. 



The vegetation of the surrounding area is of very great interest to the 

 botanist. The most striking plant of all, and the one which catches the 

 eye at once, is the giant cactus {,Cereus giganteus), a great, green-ribbed 

 column, with one or more arms projecting outwards and upwards mid- 

 way its length. Nor does one cease to wonder on extended acquaintance 

 at these remarkable products of nature — they unfailingly command the 

 attention. There is something uncanny in their sentinel-like stillness. 



