GALLS CAUSED BY GALL-WASPS 41 
May. It is greenish at first, becoming brown at maturity, 
and is covered with erect whitish hairs. It much resembles 
the gall of Andricus amenti (whose agamic generation is 
unknown), but is larger, stouter, not so pointed, and has 
longer hair. 
Andricus pilosus appears in the middle of June. The 
female attacks the axillary buds, giving rise to the arti¬ 
choke or hop gall. This gall occurs chiefly on young 
Oaks, often in large numbers on saplings. The scales of 
the leaf bud become greatly hypertrophied, and the true 
gall lies in their midst. It is small, pear-shaped, green at 
first, brown at maturity, becoming hard and woody. In its 
5 
4 
Fig. 4—Galls on Buds of the Common Oak caused by the 
PRESENCE OF THE LARVAE OF CytlipS Kolldri. (l/2.) 
Fig. 5—Galls caused by the presence of the Larvae of 
Andricus circulans in a Turkey Oak Bud. (2/1.) 
early state it is joined to the bud, later it becomes detached 
and falls to the ground. The wasp {Andricus fccundator) 
may emerge in spring, but in many cases the larva lives 
within its wooden prison for three, or even four, years 
before metamorphosis takes place. Some, for unexplained 
reasons, never change. The inquilines and parasites are 
not numerous; lists have been given by Cameron and 
others. The moth Carpocapsa Juliana is found commonly 
in these galls. 
The very familiar marble gall is situated on a terminal 
or lateral bud, and is about the size of a marble when 
full growm. It is yellowish at first, becoming brown at 
