1922] WILLAMAN & DAVISON—PLANT DISEASES 105 
Breeding Farm at Excelsior in 1918.2 In table I are given the data 
concerning the samples. 
PREPARATION OF MATERIAL.—The plums were halved or 
quartered, freed from the pits, and placed in ovens at about go°- 
95° C. until dry enough to grind. It was not thought necessary to 
use special precautions in drying, considering the nature of the 
analyses to be made. ‘The finely ground material was stored in 
bottles. The plums were rotted by sterilizing in mercuric chloride 
solution, and then inoculating with a suspension of spores by means 
TABLE 7 
DATA ON PLUM SAMPLES, 1918 
| No. of 
ao Texture 
Lab. Vacs Abbrevi-| Date — Condition of ~ of 
no. see ation | picked fruit cig rotted 
growth for fruit 
| rotting 
Resistant 
ee aad cae xX Wolf o BXWo| July 2 I Green, half grown 9 Firm 
2 urbank X Wolf 9 BXWo | Aug. 21 It Fully grown, not ripe 12 Firm 
6h Be rbank X Wolf 9 BXWo | Sept. 3 | II Ripe 10 — 
rm 
80...) Abundance XWolf 18 |AXW 18] July 2 I Green, half grown 12 Firm 
88...) Abundance X Wolf 3 AXW 18} Aug. 21 II Fully grown, not ripe 9 Hard 
pig Abundance Wolf 18 |AXW 18} Sept. 3 | III Ripe II Firm 
fy 
81...| Compass Cc July 2 I Green, half grown 6 ft 
89...| Compass C Aug. 2 II Fully grown, not ripe 7 Soft and 
wat 
93...| Compass Cc Aug. 8] III Ripe 6 ft 
82...| Sand cherry XFormosa| SCXF | July 2 Green, half grown 6 — ; 
what soit 
90...) Sand cherry XF — SCXF | Aug. 2 II Fully grown, not ripe 7 ft 
94...) Sand cherry XFormosa| SCXF | Aug. 8 | III Ripe 6 
of a hypodermic syringe, plunging the needle right to the pit. 
It required from eight to fourteen days for complete rotting, as 
shown by the tissue becoming dark brown throughout. 
METHODS OF ANALYSIS.—The moisture content of each sample 
was carefully determined at the time the other analyses were made, 
by drying to constant weight in a vacuum at 60°C. For the ash 
determination, 2 gm. samples were incinerated in platinum dishes, 
and then heated in a muffle at 550°C. until constant in weight. 
The calcium was determined in the ash by the McCRuppEN method 
(3), which has proved to be very simple and accurate. The Official 
Methods (1) were followed for total nitrogen and ether extract, 
? The writers’ thanks are due to Dr. M. J. Dorsey for his courtesies in furhishing 
€ samples. 
