THE AMERICAN BOTANIST. 
85 
Herliarium. Its interests are purely scientific and Mr. 
Vanderbilt is to be congratulated on its growth and its 
work. 
INSECT GALLS. 
BY FRANK DOBBIN. 
THE insect gall is a familiar sight to the rambler in the 
autmun fields. On twigs and leaves of the oak, the 
willows, the wild rose and the stems of golden rod, one 
cannot fail to notice these peculiar growths. That they 
are abnormal growths is at once ap[)arent. 
One of the most familiar is that enlargement of the 
stem of the golden rod just below the flowers, known as 
the golden rod ball gall ( Trypeta solid aginis, Fitch) . The 
balls are usually about an inch in diameter and have a 
pithy inside with a rounded cell in the center containing 
stem. There are two other common golden rod gallsi 
The bunch gall {Cecidomyia solid aginis Loew) which is 
produced b\* an arresting of the stalk, causing the leaves 
to accumulate in a large Ininch at the end, and the side 
gall (Trypeta polita Loew) caused hy the arresting of the 
side branches on which accumulates a small bunch of 
aborted leaves. Near the base of this bunch is the hollow 
in which the larva lives. This form is usually found on 
stalks oiSoHdago altissima. 
The ditferent species of wild rose have several forms of 
galls. One of the most common of these being the mealy 
gall {Rhodites ignota). These have a rounded woody 
bod V covered with a white mealv substance. Sometimes 
two or three grow together making a body nearly as large 
as a walnut but usually they are only about the size of a 
pea. They are found on the leaves. Another to be fonnd 
on the twigs of the wild rose is the spiny gall. {Rhodites 
bicolar) a small body one -half inch or less in diameter 
covered with long prickly spines. It is yellowish green in 
summer and brown in winter. The common cinquefoil 
