INSECT GALLS 
Rhabdophaga batatas, Walsh. Host Salix humi- 
lis, Marsh. A nodule-like swelling of the stem of the 
prairie willow. Very variable in size and shape. 
Rhabdophaga strobiloides, Walsh. Host Salix 
cordata, Muhl. <A top-shaped mass of leaves, pro- 
duced by a shortening of the stem axis of the host, 
constitutes the principal mass of this gall. 
Eurosta solidaginis, Fitch. Host Solidago cana- 
densis, L. The gall consists of a spherical swelling 
of the stem of this golden-rod. When dry it is pith- 
like in structure throughout. 
Order CoLEoPTERA. 
Podapion gallicolla, Riley. Host Pinus resinosa, 
Ait. An ellipsoidal to spherical swelling of the 
branches of red pine. 
Saperda concolor, Lec. Host Populus candicans, 
Ait. A more or less regularly ellipsoidal swelling 
of the stem or branches of the host. The producer 
emerges early in May. 
Order Hymenortersa. Family Tenthredinidae. 
Sawfly gall producers infest only the willows. 
Euura Salix gemma, Walsh. Host Salix humilis, 
Marsh. This gall is produced by the swelling of a 
lateral bud. 
Euura Salix ovum, Walsh. Host Salix cordata, 
Muhl. A monothalamous gall consisting of an elon- 
gated oval swelling on one side of a twig. 
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