12 BULLETIN 1066, U. S. DEPARTMENT OF AGRICULTURE. 



on the side of the nut (PL VI, C) and a whitish larva feeding within. 

 (PL VI, D.) The dropping of nuts from this cause is sometimes 

 very heavy. 



HISTORY AND DISTRIBUTION. 



This species was described and named in 1837 by Boheman. 9 

 Since the original description was published the species has been 

 referred to occasionally by entomologists, but it has at no time at- 

 tracted extensive notice. It has been recorded from the States of 

 New Jersey, Ohio, Virginia, West Virginia, Louisiana, Florida, and 

 the District of Columbia. 



FOOD PLANTS. 



During the last 15 years the writer has reared this curculio 

 frequently from hickory nuts in West Virginia. Pierce 10 has 

 reared it from hickory nuts in Louisiana, Apparently its attacks 

 are confined to the nuts of various species of hickory. In West Vir- 

 ginia the nuts of the pignut hickory, Hicoria glabra, seem to be pre- 

 ferred to those of other species, although shagbark hickory nuts, 

 H. ovata, are sometimes attacked extensively. Nuts of H. alba and 

 H. minima are attacked to some extent and it is probable that injury 

 may occur to the nuts of all species of hickory that grow within the 

 range of the insect. 



LIFE HISTORY. 



The egg (PL VI, B) is oblong, elliptical, translucent white, the 

 surface smooth and shiny. The average dimensions are 1 mm. long 

 by 0.6 mm. thick. The eggs hatch in from five to seven days. 



The larva (PL VI, D) is white with light brown head, full-grown 

 specimens measuring 12 mm. in length. The larvae are practically 

 identical with those of the preceding species except that they taper 

 somewhat more abruptly at the anal end than Conotrachelus retentus, 

 and the bristles, with which the body is sparsely clothed, are shorter 

 and less conspicuous than in C. juglandis. They are found feeding 

 singly in fallen nuts during the months of July and August. The 

 infested nuts drop about 20 days after oviposition takes place, 

 or about 2 weeks after the larvse begin to feed. At the time 

 of dropping, the nuts average from one-half to two-thirds grown. 



9 Boheman, C. H., In Schoenhekr, C. J. Synonymia insectorum. Genera et 

 specter curculionidum, t. 4, pars. 1, p. 429-430. 1837. 



10 PlECRCE, W. DWIGHT. O'N THE BIOLOGIES OF THE RHYNCHOPHORA OF NORTH AMERICA. 



Studies from the Zoological Laboratory of the University of Nebraska, No. 78. Nebr. 

 State Bd. Agr., Rpt. Zoologist, p. 274. 1907. 



