354 
by chance it moyed about in a limited space as in 
some nook in which it had taken up its abode. 
In such a web insects would be trapped, and thus 
might arise the habit of building webs for the 
purpose of trapping insects. Many spiders spin 
simple irregular webs composed entirely of the 
drag-line silk. From this simple type was traced 
series of specializations leading to the different 
types of complicated webs. In the making of 
some of these several different kinds of silk are 
used. 
The following officers were elected for the year 
1912: 
President—Stephen A. Forbes. 
First Vice-president—A. D. Hopkins. 
Second Vice-president—C. P. Gillette. 
Secretary-Treasurer—Alex. D. MacGillivray. 
Additional Members of Executive Committee: 
J. H. Comstock, J. B. Smith, Henry Skinner, Her- 
bert Osborn, E. D. Ball, P. P. Calvert. 
Member of Committee on Nomenclature—H. T. 
Fernald. 
The society adjourned to meet with the Amer- 
ican Association for the Advancement of Science 
at Cleveland, Ohio. 
ALEX. D,. MACGILLIVRAY, 
Secretary-Treasurer 
SOCIETIES AND ACADEMIES 
THE ACADEMY OF SCIENCE OF ST. LOUIS 
THE meeting of the Academy of Science of 
St. Louis was held at the Academy Building, Mon- 
day evening, January 15, 1912, President Engler 
in the chair. Dr. Arthur E. Ewing presented an 
illustrated account of Sanninoidea exttiosa (Say) 
and Sanninoidea opalescens (Hy. Edwards). 
After describing the varieties of the S. exitiosa 
and the difference between them and the S. opales- 
cens, giving the history of the insects and Beuten- 
miiller’s classification, examples were exhibited of 
the eggs on the bark of the tree, on the gum from 
the base of the tree, on leaves from the lower limbs 
of trees, and one on a trumpet vine leaf that grew 
a foot from the base of a tree, all of which were 
observed as they were laid and immediately col- 
lected, the collection having been made at the 
Mountainboro orchard, Mountainboro, Alabama, 
and at Gadsden, Alabama, between the first and 
the fifth of September, 1911. The exit of the 
larvee from these eggs was observed to be from 
seven to nine days, the time of the one laid on the 
trumpet vine was eight days. 
For four successive seasons the life period of 
SCIENCE 
[N.S. Vou. XXXV. No. 896 
the insect had been carefully noted at Mountain- 
boro, and it was found to confirm for northern 
Alabama the observations of Porter, Starnes and 
Sherman for Georgia and North Carolina, and 
shows that in the Southern Allegheny peach belt 
pupation begins about the first of August and the 
moth appears the last week in the same month. 
In 1908, August 4, as many full-grown borers were 
captured in this orchard of 15,000 trees as there 
were cocoons, the total number being 1,100; Au- 
gust 7, 300 cocoons were captured and as many 
borers destroyed. The same conditions obtained 
during the first week of August, 1909. In 1910 
the investigation was made later and resulted in 
the finding of 8,500 cocoons between the 20th and 
the 24th of August and very few borers. Two 
hundred of the cocoons were placed in a wire cage 
on a southern covered porch. From these 25 
moths emerged previous to September 5, 46 hbe- 
tween the 5th and the 8th inclusive, 29 between 
the 9th and the 13th, and after this only two, one 
male the 16th and another the 21st. The remainder 
failed to develop. 
Observations on the moths in the cage were that 
their activity depends greatly upon the tempera- 
ture; with it below 70° F. they are very quiet, 
and very active when it is above 80° F. At night 
they sleep with their antenne spread rather wide, 
some with the wings moderately spread, usually, 
however, with the wings near the body as when at 
rest, and the male with the tip of the abdomen 
strongly turned upward. When awake and alert 
the antenne were erect and near together as if 
indicating the facial expression of the insect. At 
night they took no notice of an electric light right 
above them when it was turned on and off. Thus 
caged they lived only three or four days. 
The 28th of August, 1911, fifty infested trees 
were examined. From the half of the cocoons the 
moths had escaped. During the examination only 
one borer was found which had not yet begun its 
cocoon. Throughout the orchard the moths were 
numerous, and in greater numbers from the Ist 
to the 5th of September. On September 13 only 
one moth was found, although a careful outlook 
was kept during the middle of the day, the time 
when the imago is most active. 
An exhibition was made of the larve at numer- 
ous ages, from the emergence from the egg to the 
time of spinning the cocoon, together with an 
example of their destructive work on the tree, and 
numerous mounted examples of the male and 
female moth of the S. exitiosa type. 
Also a cocoon was shown filled with the larve 
