20 



apparently very nearly full grown, tog-ether with some quite young- 

 which were just commencing- to burrow the stalks. No evidence 

 could be found that they passed from one stalk to another, but each 

 apparently g-ot its g-rowth within a sing-le plant. Aug-ust 8 nearly 

 all the larvfe in this field were about full g-rown, but no pupte were 

 detected; and eig-ht days later all had apparently g-ained their 

 g-rowth, but again no pupiP were found. In several plants empty 

 excavations v^ere seen, and Aug-ust 20 pup;e were detected at the 

 base of the stem and in the small root bulb. They were too larg-e 

 for the larval cavity, which had been opened out by eating- away 

 one side, the pupal cell being- completed by g-nawed chips and ex- 

 crement closely packed. On August 23d larva? of various ages, 

 tog-ether with pupse and adults of this beetle still in their pupal cells, 

 were broug-ht in by Mr. Marten from stalks of C. sirigosiis in this 

 same field. Sometimes the pupal cells were found among- the fi- 

 brous roots of the plant quite outside the cavity formed by the lar- 

 va in the stem, the walls of the cell being- then formed of compact 

 earth often intermingled with chips from the stem. On the 26th 

 of Aug-ust larvio of all ag-es were obtained, some of them scarcely 

 twice as larg-e as when first hatched, and others fully prepared for 

 pupation. Pup;e and adults were likewise found, the latter still in 

 their underg-round cells which, in some cases, were still contained 

 within the stem of the sedge, the frag-ments of the plant having- 

 been tightly packed tcg-ether to make a compact case, so smooth 

 within as to sug-g-est that it had been lined by a larval secretion. 



September 6, half-g-rown and full-sized larvie, tog-ether with 

 pupae in various stag-es of advancement, were still to be found, and 

 also eg-g-s, apparently of this beetle, placed in the lower part of the 

 outer sheath or inserted into that and the second leaf also. 

 Small round holes were seen in the g-round from which adults had 

 apparently emerged. 



From these observations it is to be inferred that the breeding- 

 period of this species is very long-, the eg-gs being- laid at intervals 

 throug-h many weeks. The larg-est larva noticed July 25 could not 

 have hatched from the egg- later than the middle of that month, 

 and the very young- of Aug-ust 26 could have been at most but 

 a few days old. Pupation and the formation of the adult by Au- 

 g-ust 23 and the subsequent disappearance of imagos from the 

 g-round, together with their occurrence in the field as late as Sep- 

 tember 16, warrant us in assuming- the hibernation of the imag-o, 

 althoug-h it is of course possible that some observed as larvw may 

 have hibernated in the pupa stag-e. There is no evidence in these 



