State Museum of Natural History. 35 



small portion of the exposed flesh being examined it was found that 

 the spores had germinated and had commenced sending out their 

 threads or mycelium. No change was observed where spores had been 

 sown on the rind. 



On the 27th the discoloration about the scar had increased in extent, 

 and the spot where the spores had been planted on the flesh was sur- 

 rounded on all sides by a rot-discoloration one-fourth of an inch broad. 

 Nothing has yet come of the spores planted on the rind, nor did they 

 appear afterward to produce any effect. On the 28th both rot spots 

 had increased in size, and the flesh wound where the spores Avere 

 planted was covered with a fine crop of the Oidium. On the 30th the 

 two rot spots had run together and the scar was also covered with the 

 oidium. Oct. 1st, nearly the whole peach was discolored. Oct. 2d, 

 the whole peach was discolored and the Oidium had broken out in one 

 new spot. 



Sept. 27. A hard, sound peach was inoculated in two places by 

 making slight incisions under the rind, inserting in them the spores 

 of the Oidium and then pressing down the rind closely in its original 

 place, to shut off as much as possible exposure to the external air. Spores 

 were also planted on the uninjured rind and moistened with water. On 

 the next day the places of inoculation were surrounded by discolored rot 

 spots. No change appeared where the spores were planted on the rind, 

 nor did these spores afterward produce any effect. Sept. 30th. The 

 two rot spots about the places of inoculation have run together and 

 now occupy about one-half the peach. Oct. 1st. The rot has ex- 

 tended and reached the stem-scar of the peach, and there a nice crop 

 of the Oidium has made its appearance. No Oidium has appeared in 

 the two places of inoculation. Oct. 2d. The rot has extended and 

 the Oidium has broken out in a new place on the part of the peach 

 opposite the stem-scar. 



►Sept. 27. A hard, sound peach was cut into halves and the Oidium 

 spores were planted in a small spotin the cut flesh of one of the halves. 

 On the 28th there was a discolored spot about the place where the 

 spores were planted, but not elsewhere. The 29th, being Sunday, no 

 observation was taken. On the 30th about one-third of the cut sur- 

 face was discolored, the discoloration being only on the side where the 

 spores were planted. Also the Oidium has appeared. Oct. 1st. The 

 discoloration has extended and more Oidium has developed. Oct. 2d. 

 The discoloration has extended but little, probably from lack of moist- 

 ure, as the peach is becoming dry. The implanted side is still un- 

 harmed, though considerably dried. 



From these three simple experiments the following deductions are 

 made: First, the Oidium does produce a kind of rot in the peach; 

 Second, the spores do not affect the peach when planted on the unin- 

 jured skin or rind ; Third, when planted on the freshly-exposed flesh 

 they germinate most readily and reproduce themselves in about three 

 days. These results might possibly be somewhat modified if the ex- 

 periments were, made on other fruits, but essentially I believe they 

 would only be confirmed. 



The names that have been applied to this fungus by mycologists at 

 different times are numerous. Among them are Torula fructigena, 



