78 SILVA OF NORTH AMERICA. ROSACEH 
Counties, California.’ It grows usually in deep rich soil in the neighborhood of streams, often forming 
almost impenetrable thickets of considerable extent, and attains its greatest size in the valleys of Wash- 
ington and Oregon. 
The wood of Pyrus rivularis is heavy, hard, and very close-grained, with a satiny surface suscep- 
tible of receiving a beautiful polish; it contains numerous obscure medullary rays, and is light brown 
tinged with red, with thick lighter colored sapwood composed of twenty-five to thirty layers of annual 
growth. The specific gravity of the absolutely dry wood is 0.8316, a cubic foot weighing 51.83 pounds. 
It is employed for mallets, malls, the handles of tools, and the bearings of machinery. 
The fruit, which has a pleasant subacid flavor when fully ripe, is gathered and consumed by the 
Indians.’ 
Archibald Menzies,’ who sailed with Vancouver as surgeon and naturalist late in the last century, 
appears to have been the first botanist to notice Pyrus rivularis, although its character was not distin- 
guished until fifty years later." In 1882 it was introduced from Oregon into the Arnold Arboretum, 
where it is perfectly hardy and flowers abundantly every year.5 
1 Greene, Fl. Francis. i. 53. 
2 “The fruit of the Crab-apple (Pyrus rivularis) is prepared for 
food by being wrapt in leaves and preserved in bags all winter. 
When the apples have become sweet, they are cooked by digging a 
hole in the ground, covering it over thickly with green leaves and 
a layer of earth or sand, and then kindling a fire above them.” 
(R. Brown (Campst.), Trans. Bot. Soc. Edinburgh, ix. 383.) 
5 See ii. 90, 
* Probably the earliest printed reference to this tree is in Georgi’s 
Geographisch-Physikalische und Naturhistorische Beschreibung des 
Russischen Reichs (pt. iii. iv. 1015), published in 1800, where the 
wild Apple-tree seen by Schelechow on the Aleutian Islands is 
mentioned, but is regarded as a variety of the common Apple- 
tree. 
dingly rare in Europ 
5 Pyrus rivularis is gardens, and. 
does not appear to have attracted the attention of European horti- 
It is cultivated, however, in the garden of the Forest 
School at Miinden, where it flowers and produces fruit. 
culturists. 
EXPLANATION OF THE PLATE. 
Puare CLXX. Pyrvus RIVULARIS. 
1. A flowering branch, natural size. 
2. Vertical section of a flower, the petals removed, enlarged. 
8. Cross section of an ovary, enlarged. 
4. A fruiting branch, natural size. 
5. A fruit divided transversely, enlarged. 
6. A winter branchlet, natural size. 
