50 KANSAS ACADEMY OF SCIENCE. 
sands of them so small as to be invisible even with the best telescopes, many of 
which move in orbits quite adjacent to the orbits of both Jupiter and Mars. Not. 
only may some of them become satellites of the two planets, but there may be 
satellites of the two, invisible as yet, that were once asteroids pursuing their way 
around the Sun, influenced by the perturbing influences of either Jupiter or 
Mars. The asteriodal belt may, for all we know, extend all the way from the 
orbit of Mars to that of Jupiter, and the liability that some of them should be 
captured by their giant neighbors becomes almost, if not altogether, a certainty. ~ 
Then, if all the foregoing be true, it may be affirmed with a reasonable degree 
of probability that the two moons of Mars, Deimos and Phobos, at one time in 
the far distant past were members of the asteroidal group. Their size also 
seems to indicate their origin, one of which, the larger being not more than 16 
miles in diameter, and possibly only seven miles. The time of revolution of Pho- . 
bos, the inner moon, is 7 hours 39 minutes. That is to say, it revolves about 
Mars a little more than three times every 24 hours, and presents all the different 
phases of new moon, first quarter, full moon, and last quarter, at each revolu- 
tion. Young says that ‘‘this rapidity of revolution raises important questions as 
to the theory of the development of the solar system, and requires modification 
of the views which have been held up to the time of their discovery. If the 
nebular hypothesis is true, a shortening of the satellite’s period or a lengthening: 
of the planet’s day must have occurred since the satellites came into being.”’ 
Now, a shortening of the satellite’s period of revolution indicates that its orbit has 
been contracted to smaller dimensions; and this shortening may have been going 
on for a long time, so that at the time the shortening began the satellite was far 
enough away to be in the zone of asteroids; in fact, an asteroid itself. 
The conclusion, therefore, which was referred to in the beginning of this dis- 
cussion, is that, owing to the proximity of the asteroidal belt, the intersection of 
the orbits of Mars and Authra, the small size of the asteroids and the moons of 
Mars, the red planet captured its moons from the asteroidal group. And, if this 
be so, then Jupiter some time in the past has done a like thing. 
The future, supplied with more powerful telescopes and appliances, may re- 
veal to our gaze more moons still revolving about the two planets, of which some 
were captured, and since that time have been playing the role of satellites. 
NOTES ON INJURIOUS INSECTS. 
By S. J. Hunter, Lawrence, Kan. Read beforeSthe Academy January 1, 1897. 
The year just closing has witnessed the recurrence of some familiar insect 
pests, and the presence of forms strange to many because of previous scarcity in 
this locality. 
The notes that follow are based upon correspondence received at the depart- 
ment of entomology and upon field observations made by members of the depart- 
ment. 
ArRMy-worM (Leucania unipunctata). 
First appearance in state, 1876; again, 1891. This year present in damaging 
numbers in Douglas, Leavenworth, Ottawa, Brown, Harvey, Cloud and Ells- 
worth counties. 
- The worm is the larva of a fawn-colored moth of variable size, average having 
wing expanse of an inch and a half. Front wings freely sprinkled with black 
