96 MR. C. B. PLOWRIGHT ON CERTAIN 
from which the infected leaves had fallen showed marked 
swellings; these continued to increase ; and from them on 1st 
April, 1886, were developed the characteristic Gymnosporangium 
clavarieforme. Thus it is evident that two years are required 
for the development of the Gymnosporangium from the time the 
Restelia-spores enter the leaves until the teleutospores are 
produced. 
GYMNOSPORANGIUM CLAVARIEFORME. 
t 
No. | Infecting material. Plant infected. Date of Date offi id 
4. | G. clavarieforme. Crategus Oxyacantha.| 6 April | 24 April 
5. » 2 ” » 7 April » 
15. » » » » 17 April 6 May 
27. 3» 35 ” „ 11 May 21 May 
161. » » » " 2June | 11 June 
316. » » » » 24 April | 10 May 
317. » 39 ” 23 „ » 
318. » ” ” ” ” » 
319. » 2? » » » » 
320. » » » » » 3? 
349. » 93 » » 16 May 29 May 
316. » » » » 28 May 7 June 
491. » 7 » » 25 April | 5 May 
492. » » » » » 10 May 
628, » " » » 18 May | 29 May 
639. » » » » 9 June 24 June 
410. | Restelia lacerata. Juniperus communis. | 25 June 1 July 
411. » » » » » 8 July 
24. | G. clavarieforme. Pyrus communis. 10 May 3 June 
28. ?5 35 35 » 11 May 
160. ” ” » ” 2 June 
34.| „ is r , 16 May | 27 May 
490. » LEJ „ 39 25 April 
640. » » » » 9 June — 
641. ”? „ „ ” 39 —— 
345. » » Pyrus Malus. 16 May — 
348. » » P. Aucuparia. » — 
Gymnosporangium juniperinum, Fr. 
This fungus does not occur near King’s Lynn. I have to thank 
my friends the Rev. Dr. Keith, of Forres, and the Rev. John 
Stevenson, of Glamis, for sending me material from Scotland. Had 
the fungus occurred nearer, more experiments would have been 
made with it, and most likely with a greater degree of success. 
In 7 experiments the Gymnosporangium was placed on Pyrus 
Aucuparia, and in five the Restelia was produced. In some of 
these experiments more than one Sorbus-plant was infected; iu 
one instance, in which the Restelia was abundant upon the leaves 
in the autumn of 1882, I observed in the following April a single 
