A PARASITIC BOTRYTIS ON PEPPER AND LETTUCE. 47 
Under the name B. Douglasii, Tubeuf (59) describes a 
disease of the Douglas fir (Pseudotsuga Douglasii). It is 
characterized by the withering, curling up and death of the 
shoots toward the tips of young seedlings and the lower twigs 
of older trees. In the fall, sclerotia about the size of pinheads 
break through the epidermis under the old bud scales and on 
the needles. When placed in a moist chamber tufts of conid- 
iophores immediately arise from the sclerotia. The conidia 
germinate directly in water and infect young plants, which 
are killed in a few days. Tubeuf also reports this same fun- 
gus on Prunus triloba and Juniperus communis.2 Ritzema 
Bos (45) found that B. Douglasii was parasitic on a number 
of conifers. Smith (48), while working in Europe, observed 
a similar infection on the linden, attributing it to B. cinerea. 
Brooks and Bartlett (12), in England, described a disease 
of the gooseberry due to Botrytis, its chief characteristic being 
the ability to penetrate the woody tissues of the plant. The 
first indication of the trouble is the wilting of the foliage, 
followed by the death of the branches attacked. Sclerotia 
were found beneath the bark, and in some cases conidia. 
Botrytis cinerea seems to be the less frequent cause of the 
lettuce “drop” in the greenhouse, although it is a more seri- 
ous parasite than is generally supposed. Since Humphrey 
(27) reported it in Massachusetts in 1892, it has been observed 
in at least ten states, causing more or less loss. The disease is 
especially destructive in the lettuce-growing centers along the 
Atlantic coast. Up to 1900, Botrytis cinerea was supposed to 
be the sole cause of the “drop.”’ However, Smith (48), who 
had been working on the problem for a number of years, 
found that most of the‘‘drop” in Massachusetts was not due 
to Botrytis, as generally believed, but to 8. Libertiana. Up 
to the present time there is still considerable doubt as to which 
form is the primary cause, although it seems that both fungi 
are capable of infecting the lettuce under favorable conditions. 
Humphrey (27) described a typical attack of Botrytis on 
3 From his figures, B. Douglasii appears to be identical with 
B. cinerea. 
