700 Miller .— A Physiological Study of the 
were placed in the greenhouse, where the temperature was kept between 
and 75° F. 
Most of the investigations on the germination of oily seeds have been 
limited to the early stages of the seedlings before they have reached the 
surface of the ground. The few investigations that have been made on 
plants of this kind at a more advanced stage have been made on seedlings 
which have been grown in darkness. As it is a well-known fact that plants 
which are grown in darkness are abnormal, chemically as well as morpho¬ 
logically, one should be careful in accepting the results obtained under such 
conditions as indicating the processes which take place in the seedling under 
normal conditions. 
Since it was thought advisable to examine the seedlings of the sun¬ 
flower at several stages after they had reached the surface of the soil, 
a method was sought whereby the seedlings could have the normal tonic 
influence of the sunlight and at the same time be unable to carry on the 
processes of photosynthesis. For these advanced stages, the seeds were 
planted in the sand in flower-pots or pans which had been coated on the 
inside with a layer of paraffin. After the seedlings had reached the surface 
of the sand, the pans and pots containing them were placed in the apparatus 
as shown in Fig. 1. 
This apparatus consisted of twelve large glass jars, placed in large tin 
pans and connected with each other by means of glass tubing. The jars 
were sealed with water and the water then covered with a layer of engine 
oil about | cm. in thickness. This layer of oil retarded the evaporation of 
the water into the jars above, and thus prevented abnormal conditions 
which might arise from an excess of moisture. At intervals in the con¬ 
nexions between the jars, wash-bottles containing strong sulphuric acid 
were inserted in order to take up the moisture in the air due to the trans¬ 
piration of the seedlings, and the evaporation from the sand. The series of 
jars was connected at one end to a filter pump, and a stream of air con¬ 
tinually pulled through the apparatus while the seedlings were contained in 
