664 
DIPTERA. 
the West Indies to China and India has hitherto not been a direct one, 
but has passed by a long circuit either to the North or to the South. 
When the American inter-oceanic canal has been constructed, there will 
be direct and rapid communication between the present yellow-fever 
centres and Asia. With this more direct and more rapid communication 
there will arise a corresponding risk of spreading yellow fever into a 
huge section of tropical humanity which has hitherto enjoyed exemption 
from one of the deadliest diseases afflicting mankind. An infected 
mosquito (and Stegomyia fascmta, according to Giles, is a good traveller), 
either shipped by accident or brought on board by some thoughtless or 
malicious person, could easily be conveyed alive to the shores of Asia, 
and would suffice to set, so to speak, the whole of the tropical section of 
the Eastern hemisphere in a blaze. The history of the spread of disease 
by the rapid methods of modern travel is full of examples that should 
serve as a warning to our rulers and responsible sanitary authorities. 
Let us hope that before the central American canal is completed this 
important matter will receive the attention it demands, and that due 
care will be exercised that America does not reciprocate the introduction 
of cholera from Asia by a return gift of yellow fever.” 
