262 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 12 



abdominal segments show clear spaces much like Pyrausta penitalis 

 (Fig. 13; no. 28, 6). 



Pyralidce. — This family contains many injurious pests and among 

 them several well-known borers. The larvae are distinguished by the 

 two setae in front of the prothoracic spiracle, or slightly below it 

 (Fig. 12, nos. 15, 18, 24) and the arrangement of hooks on the prolegs 

 (Fig. 12, nos. 16, 21, 25) which are nearly always of three sizes, arranged 

 in a complete circle, or in a broken circle, open at the lateral margin. 

 In three of the subfamilies, Phycitinae, Crambinse and Pyraustinae, are 

 species with the boring habit. There is considerable individual varia- 

 tion in nearly all the species of this family making the classification 

 exceedingly difficult. It will be impossible to make anything like a. 

 good classification, until a larger number of species have been reared. 

 The following key will separate the principal genera. 



a Hooks of prolegs arranged in a complete circle and of three sizes (Fig. 12, no. 16) 

 6 Adfrontal pieces reaching the vertical triangle (see Fig. 13, no. 29) which is very- 

 large ; eight setse present on each half of the ninth abdominal segment and 



not arranged in a straight hne Elasmopalpus 



bb Adfrontal pieces not reaching the vertical triangle, which is of normal size; 

 six setse present on each half of the ninth abdominal segment, arranged 

 in a straight line, 

 c Spiracular setse always below the level of the thoracic spiracle (Fig. 12, 

 no. 18) ; body never with skin sculpturing, as in Fig. 13, nos. 33, 34, but 

 smooth, nor with a chitinized spot caudad of the spiracle on each 

 proleg-bearing segment (see Fig. 13, no. 28, s. p.) body always with 



prominent black or brown spots around the setse Diatraea 



cc Spiracular setse seldom below the level of the thoracic spiracle (Fig. 12, no. 15), 

 usually at least one of them in front of it, if both are below the level of 

 the spiracle then there is a very distinct chitinized mark caudad of the 

 spiracle on each proleg-bearing segment; skin often with sculpturing as 



in Fig. 14, no. 33 Crambus 



aa Hooks of prolegs not arranged in a complete circle (Fig. 13, nos. 21, 25) 



b Set« of prothorax and ocelh arranged as Fig. 13, nos. 20, 22; thorax distinctly- 

 narrowed towards the head, which is comparatively small Diaphania 



bb Setse of prothorax and ocelli arranged as in Fig. 12, nos. 24, 26; thoracic seg- 

 ments of approximately the same width ; head of normal size .... Pyrausta 



Phycitince, — The only member of this family likely to be met is 

 Elasmopalpus lignosellus, the lesser cornstalk-borer. It is easily 

 distinguished by the character given in the key, also by the peculiar 

 striped and banded appearance. One of the setae on the lateral sur- 

 face of the ninth abdominal segment is small and weak and should not 

 be overlooked. Etiella zinckenella, reported as boring in beans in the 

 west, belongs here, but is comparatively rare. Another borer in the 

 stems of beans, Monoptilota nubilella, forms galls, and is not considered 

 here. 



