530 Philippine Journal of Science 1919 
nied the specimens in the preserving fluid, the galls and insects 
being given the same number in the accession record. 
Longitudinal and cross sections were made of the mature 
galls, and these were drawn to show the details in structure and 
the mechanism peculiar to each case. 
No hard and fast rule can be laid down as to the methods to 
be followed in breeding the insects from their galls. Condi- 
tions were different in each case, and laboratory methods had to 
be modified accordingly. In general, battery jars with fine 
muslin held on by elastic bands at the top proved to be the best 
form of breeding receptacle, a decided advantage in favor of 
these being that the green parts of the plants were kept ade- 
quately exposed to the light and that inspection and cleaning 
were easy. During dry months the materials had to be mois- 
tened at least once a day by spraying them with water from a 
small hand atomizer. Care was taken not to wet the plants too 
much, for then decay would set in, or the adult insects on emer- 
gence would be entrapped by the film of water on the plant sur- 
face or the inner wall of the jar and spoiled. The jars were 
inspected every morning and the adults caught by means of a 
short test tube. The removal of the adults as soon as they 
emerged was a necessary measure, because when allowed to stay 
in the vessel for a longer time many of them would be lost or 
badly mutilated among the moist plant materials. 
Throughout the progress of the work precautions were taken 
against certain small spiders which, when accidentally intro- 
duced into the jar with the plant materials, would prey upon the 
gall insects as fast as the latter emerged. As a measure against 
this pest, the pieces of plants were thoroughly shaken, one by 
one, before being placed into the jars, and a constant watch was 
kept for the appearance of any of the spiders that might have 
hatched from eggs accidentally introduced. 
Another piece of apparatus used consisted of a light-tight 
cardboard box with the mouth ends of test tubes or vials inserted 
into one side. This device was supposed to work on the prin- 
ciple that most insects are attracted to the light ; and the interior 
of the box being dark, except at the insertion of the glass tubes, 
the insects on emerging were supposed to enter the latter. The 
apparatus had been used with good results and had been 
indorsed by the California Board of Horticulture and by the 
cotton-boll weevil investigators.? The results with this device in 
* Banks, Nathan, Directions for Collecting and Preserving Insects, Bull. 
U. S. Nat. Mus. 67 (1909) 115, with figure. 
