RARE TREES AND SHRUBS IN THE ARNOLD ARBORETUM, U.S.A. 29 



The colour is dark red ; many are sour, but some varieties are 

 but slightly acid, or even quite sweet, and the American pomolo- 

 gists are confident of getting some still more improved varieties 

 in time. The erect form of this species — the Chicago form, as 

 they call it — is the best. A close ally, P. Baseyi, or it may 

 be a new form of P. pumila, was recently found in the Rocky 

 Mountains. 



Primus maritima, 10 feet high, is very fine when in flower ; 

 Prunus americanus and P. nigra have small brilliant fruits, 

 and some varieties are quite edible. The Cherry-like fruits of 

 P. alleghenensis make excellent preserves, and the plant is a 

 very free bloomer ; so also are P. pendula and P. Miqtteliana, 

 both Japanese or Chinese species. 



Among the tall Spirreas I noticed as a fine bush S. Tobolski- 

 ana. It is in the Sorbifolia section (Sorbaria), but the foliage is 

 more plicate. One recommendation of it is that it flowers ten or 

 twelve days later than S. Lindleyana. 



A good many botanical species of the Rose are to be seen, not 

 in the Arboretum, but in other places round Boston. Near 

 the track of the Boston and Albany Railroad many banks and 

 beds are planted with a single form of B. humilis, an elegant 

 little plant, very graceful, and of a chaste delicacy of colour. It 

 may be a little deficient in leaf, so that the soil is not as com- 

 pletely hidden as with our garden Roses ; a double form of this 

 species is a charming little thing of a very light pink colour, 

 nearly blush. Rosa Watsoniana, with deeply cut, almost dis- 

 sected leaves, is very curious and pretty, even without flowers. 

 It appears to be a very good stock for grafting. A new species 

 from Cashmere was under observation, as yet without a recog- 

 nised name. It seemed to me different from my own seedlings 

 from the same country. The American species, pisocarpa, 

 setigera, foliosa, nitida, and lucida, are now known to many 

 European amateurs. They are generally noticeable by the 

 holding of their bright berries far into the winter. Some inter- 

 esting crosses were made in the Arboretum between B. rngosa 

 and B. microphylla, between B. Vichuraiana and B. multi flora, 

 &c. Some of the hybrids are described or mentioned in the 

 later volumes of the Garden and Forest. 



Among the Pyrus the finest specimens are in the Professor's 

 garden in Brookline, being 12 to 15 years old. The newest to 



