Bailey . — Puccinia malvacearum and the Mycoplasm Theory. 189 
In spite of these precautions, Collembolae did again appear, though 
very sparingly. This must be attributed to the fact that the plants were 
watered with tap-water owing to the impossibility of sterilizing sufficient 
water to meet the daily needs of the plants in summer. 
The globes and tubes were sterilized with formalin vapour as before, 
and the corks and all rubber parts were immersed in rectified spirit for 
Fig. 2 . Hollyhock Globe No. 9 and Control Pot No. 7 (from a photograph taken on 
June 27, 1914). 
the same purpose. In addition to the formalin treatment, all the glass- 
ware was rinsed over with rectified spirit shortly before starting the 
experiment. 
The seed used in the globes and pat “controls for this experiment was 
collected in October 1913 from some double hollyhocks with reddish 
magenta flowers, which had shown a considerable amount of rust on leaves, 
stems, and calyx, and also on the carpels themselves during the foregoing 
season. 
In order to avoid trouble from seeds failing to germinate, they were 
