68 o 
Journal of Agricultural Research 
Vol. XXIII, Na 9 
the crop was subject. Only one was reported as occurring in America, 
a seedling blight in Mississippi in 1892 {18). Apparently but little work 
had been done on the disease at the time, and as the crop was not con¬ 
tinued in later years no further investigations were made. The common 
dooryard castor bean of the South, “ Palma Christi” as it is widely 
called, has always been so free from disease that it was commonly be¬ 
lieved to be immune. In fact, there was a widespread superstition that 
it had a beneficial effect on other crops and even on chickens, around 
whose yards it is often planted. It was believed that the castor bean 
kept both kitchen garden and chickens from attack by insect pests. 
Outside of America the most serious disease reported was a Phytoph- 
thora seedling disease and leaf blight in India, described by Dastur in 
19 1 3 (6) • A few other minor diseases including a damping-off of seedlings, 
a rust, and a leaf spot, also occur in India. The diseases on the whole 
were not abundant and not serious. In this connection Dastur says in 
his paper ( 6 , p. 178): 
Though the castor-oil plant is so widely distributed, still no important fungus 
pest, except the rust, has been recorded as attacking this crop. 
Thus, in so far as plant diseases were concerned, the outlook was good 
for a successful season. Early in the summer, however, a number of 
pests appeared and required the attention of both entomologists and 
plant pathologists. The first alarm was caused by an outbreak of the 
semitropical army worm Xylomyges eridania Cr. 4 It practically stripped 
large portions of some fields of all green parts, resulting in the death of 
many of the plants. This was followed by the bacterial wilt, an account 
of which has been published by Smith and Godfrey ( 14 ). This, though 
widespread in its distribution, did not cause a very high percentage of 
loss. A few other insects made their appearance, particularly the red 
spider ( Tetranychus quinquenychus McGregor) and the pink com worm 
(Pyroderces rileyi Wals.) 4 In addition, two leaf spots made their appear¬ 
ance, one caused by Cercospora ricinelli Sacc. and Berl. (4) and the other 
by a bacterium. Neither was very serious. Finally, in July a gray mold 
appeared upon the inflorescence as the most serious menace of all. 
Members of the State Plant Board of Florida first reported its occurrence 
in different parts of the State to their headquarters at Gainesville. 
Entomologists who were combating the semitropical army worm noticed 
the increased seriousness of the gray mold as the rainy season advanced. 
The disease became more widespread and definitely more destructive. 
Specimens were sent to Washington to the Office of Pathological Collec¬ 
tions, and the fungus was found to be a new species of Botrytis. Prof. 
H. E. Stevens, of the Florida Experiment Station, first published a report 
of the disease ( i6 y 17). A brief mention of it was also made in a Cuban 
publication (4). Later the writer, who was assigned to the investigation 
of the problem by the Bureau of Plant Industry, published a description 
of the causal organism (jo). 
Inasmuch as this castor bean disease was a new one in America, and 
as its development was gradual during the season, from a few sporadic 
primary infections to widespread destructiveness, the writer has 
attempted to treat the different phases of his investigations in so far as 
practicable in chronologic order, in order to better record its interesting 
history. 
* Kisuuk, Max, Jr. insects affecting the castor on, plant. (Manuscript in Bur. Ent., U. S. Dept. 
Agr.) 
