Annual report of the Board of Regents of the Smithsonian Institution . eir first effort is to extricate themselves from the nar-row confines of the egg nest. It seems unlikely that enough lightcan penetrate the depths of this chamber to guide them to the exit,but once out and divested of their encumbering embryonic clothesthey are irresistably drawn in the direction of the strongest light,even though this takes them upward, just the opposite of their des-tined course. But when this instinct has served its purpose and hastaken the creatures to the port of freest passage to the earth, all theirl
Annual report of the Board of Regents of the Smithsonian Institution . eir first effort is to extricate themselves from the nar-row confines of the egg nest. It seems unlikely that enough lightcan penetrate the depths of this chamber to guide them to the exit,but once out and divested of their encumbering embryonic clothesthey are irresistably drawn in the direction of the strongest light,even though this takes them upward, just the opposite of their des-tined course. But when this instinct has served its purpose and hastaken the creatures to the port of freest passage to the earth, all theirlove of light is lost or swallowed up in the call to reenter some darkhole, narrower even than the one so recently left by such physicalexertion. When the young cicadas have entered the earth we practically haveto say good-by to them till their return. Yet this recurring event isever full of interest to us, for, as much as the cicadas have beenstudied, it seems that there is still plenty to be learned from themeach time they make their visit to our part of the Fig, 9.—Young cicada larva, or nymph, ready to enter the ground (greatly magnified), ENTOMOLOGY AND THE By Dr. L. O. Howard,Chief, Bureau of Entomology, V. 8. Department of Agriculture. Rather frequently during the past 18 months, meeting friends,they have said, by way of casual conversation, I imagine that thewar does not affect your work especially. They did not stop tothink of the very great importance of insects in the carriage of certaindiseases, the ease and frequency of such transfer becoming intensi-fied wherever great bodies of men are brought together, as in greatconstruction projects, and especially in great armies. They did notrealize, entirely aside from the especial diseases of this character metwith by the troops in Africa, Mesopotamia, and in the region ofSalonica, that even upon the western front, in a good temperateclimate, warfare under trench conditions was rendered much moredifficult by
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