82 
Peirce. — A Contribution to the 
much dryer, and of course the illumination which these plants 
received came mainly from the side. Those plants which 
remained in the greenhouse throve fairly well, both hosts and 
parasites, but not so well as those which had been sown at the 
same time and in similar soil out of doors, while those in the 
laboratory were plainly unhealthy. Since the hosts did not 
flourish, the parasites necessarily suffered with them. There 
were in these three sets of plants three colours : those growing 
out of doors on healthy, thriving Flax-plants were not only 
large and strong in appearance, but they were also of the 
typical pale orange colour ; those in the greenhouse were, 
like their hosts, smaller in size and evidently weaker, and 
their colour was pale yellow tinged with green ; those in the 
laboratory were the smallest and weakest, and had a decided 
green colour. 
If one cuts off the tips (say eight centimetres long) of 
healthy branches of a Cuscuta and puts them with their cut 
ends, some in water, and others in a decoction of the usual host 
(for convenience I used C. glomerata and C. europaea and 
their hosts, Impatiens and Chrysanthemum ), cutting off under 
the surface of the two liquids about one centimetre from the 
end of each in order to ensure as perfect conduction of the 
liquids into the branches as possible, one will notice that 
within eighteen hours the colour has changed, becoming less 
deep orange ; within forty-eight hours they have a plainly 
green hue ; and still later both sets of cuttings will have 
become nearly as intensely green as the leaves of their usual 
foster-plants. Those cuttings kept in glasses of water merely, 
grow somewhat in length, little if any in thickness, but cease 
within three days to grow at all. Those in the decoction take 
on the green colour not quite so rapidly, though within a few 
hours of the others, grow somewhat in thickness, considerably 
in length, but they too presently cease to grow, and become 
as deep green as the others. Finally all die. From the water, 
which was from the general supply of the city (Leipzig), and 
even from the decoction, only small quantities of organic 
substances could be absorbed by the cuttings, and in self- 
