MONOGRAPH OF THE GENUS SAPERDA yj 



PLATE 3 



1 Portion of elm bark illustrating- the work of the larva of the 



elm borer, Saperda tridentata. It will be seen 

 that many of the borings are in dead tissues, and that a 

 few extend into the living bark, which apparently gradu- 

 ally dies and permits the insect to extend its operations 

 over a considerable area. 



2 Piece of hickory bark illustrating the work of the larva of 



S. discoidea. The white sawdust excavated from a 

 pupal chamber made in the wood is shown at a, and a 

 pupal chamber in the bark is represented at ??. 



3 S. tridentata 



4 S. i m i t a n s 



5 S. discoidea, female 



6 S. discoidea, male 



PLATE 4 



Saperda cretata and concolor 



Spotted appletree and vuillow borers 



1 Work of S. cretata in thorn, showing the irregular char- 



acter of its galleries, and the different depths at which they 

 occur 



2 Adult beetle 



3 S. concolor, enlarged 



4 Work of this species or possibly S. tulari in Arizona 



willow. This illustration represents the peculiar gall, the 

 general form of the galleries and pupal cell, with the exit 

 hole in section. 



PLATE 5 



Saperda vestita and obliqua 



Linden and alder borers 



1 Portion of the base of a linden, showing the work of the 



larva of S. vestita, and at a the circular exit hole of 

 the adult 



2 A small alder stem, showing the enlargement produced by 



the larva of S. o b 1 i q u a a year after the stem had been 

 deserted 



3 An alder stem showing the external appearance, indicating 



recent operations of the larva of S. obliqua and at 

 b the pupal cell with the mass of borings blocking one end 



