140 THE CANADIAN ENTOMOLOGIST. 



may drill a cavity furiher on than its predecessor. Twenty minutes proves 

 sufficient for ensconcing themselves from view. 



The newly-hatched larva is of the usual delicate, semilooping char- 

 acter. The second stage finds them in a well-developed gall, which 

 lengthens and enlarges as subsequerrt conditions demand. The third 

 stage shows the typical Papaipema attributes in evidence, and we are able 

 to place the larva in one of the tiiree sections into which the group is 

 divisible. The fourth stage is entered about July i, and we Und a larva 

 belonging to the so-called nitela series, in which the dorsal line alone is 

 unbroken and continuous. The colour is dark purple-lake, upon which 

 the usual longitudinal dorsal, subdorsal and substigmatal lines show con- 

 trastingly drawn in white. The two latter stop abruptly on either side of 

 the first four abdominal segments. The general features are noimal ; the 

 thoracic shield edged with black, which continues as a noticeable line 

 down the side of head. Spiracles black, tubercles not prominent. 



In the penultimate stage we have a larva showing ronsiderai)le 

 individuality. The body is less cylindrical than usual, and is much 

 flattened ventrally, length _ n i^^'^'- Htad noiinal, side line has 

 disappeared. The wrinkled skin on the three thoracic joints accentuates 

 the slight constriction here. All tubercles bear well-developed seise, 

 plainly seen without a lens, and is a feature not equalled by other species. 

 Tubercle iv a, on seventh abdominal segment, is wanting in this species. 

 Neither spiracles nor tubercles are strongly shown, being nearly 

 concolorous with the body, which is a pale brownish-clay colour. Dorsal 

 line is alone unbroken. 



At matnrity the insect larva measures from 38 to 40 mm., and 

 attains full growth about July 20th. 'i'he colour has faded to a neutral 

 ti'anslucence, the principal comparative feature being the absence of the 

 accessory tubercle iv a on joint ten. Pupation occurs in the ground, and 

 lasts about twenty-five days. 



The pupa is normal, more tapering posteriorly than some others ; at 

 the anal extremity are two divergent, slightly-hooked spines. 



Considering the diameter of Hop-vines, the gall produced is rather 

 singular. It takes the form of a cigar-shaped enlargement, from three to 

 six inches in length and a half inch in diameter. The twining proj^ensity 

 of the vine makes it assume a crescent shape usually, and the larva 

 always maintains a very large aperture at the lower end for ventilation and 

 housecleaning. At maturity a large ragged opening is made at the upper 

 end, through which the larva escapes. It is then eaten through to a very 



