EGG AND MANNER OF OVIPOSITION OF LYCTUS 

 PLANICOIvLIS ' 



By Thomas E. Snyder, 

 Assistant in Forest Entomology, Bureau of Entomology 



HISTORICAL SUMMARY 



The so-called "powder-post" injury to seasoned wood products is 

 widely distributed over the world. Of the various beetles causing this 

 type of injury, species of the genus Lyctus Fab. are by far the most 

 important. While these beetles and their damage have an extensive 

 literature, the place and manner of oviposition have remained obscure. 

 Heeger (3),^ in 1853, described and figured the egg, larva, and pupa of 

 a beetle attributed to a European species, Lyctus pubescens Panzer. 

 Duges (i),^ in 1883, described and figured the larva, pupa, and adult of 

 L. planicollis Le Conte (?), proving that Heeger was in error in 

 ascribing the larva he figured to the genus Lyctus. Xambeu (7), in 

 1898, described the egg and manner of oviposition of L. linearis Goeze 

 (canaliculatus Fab.). Recently the eggs of the native species, L. plani- 

 collis of the southern United States, have been found by the writer. 

 This egg is very unlike that described and figured by Heeger as 

 the egg of L. pubescens, and it differs from the egg of L. canaliculatus 

 as described by Xambeu, being of a most unusual type for Coleoptera. 



The following brief notes on the mating and oviposition of the southern 

 species (L. planicollis Le Conte) were made on material being reared 

 either at Washington, D. C, or at Falls Church, Va., in buildings kept 

 dry and at a temperature above freezing. 



LIFE CYCLE 



MATING 



The beetle passes the winter in the larval stage, but in cold weather 

 the larvae are more or less dormant and infested stock may consequently 

 pass unnoticed. Mating takes place and the eggs are deposited soon after 

 the adult beetles emerge from the wood in the spring. At Washington, 

 D. C, and Falls Church, Va., the first adults emerged from infested wood 

 in rearing cages during the last part of February and first part of March, 



1 The specimens on which this paper is based were identified by Mr. W. S. Fisher, Specialist on Forest 

 Coleoptera, of the Branch of Forest Insect Investigations, Bureau of Entomology. 



2 Reference is made by number to "Literature cited," p. 276. 



^ According to Duges, the material on which his paper was based had been determined by two different 

 authorities as Lyctus planicollis Le Conte (of southern U. S.) and carbonarius Waltl. (of Mexico and Florida). 

 Dugfes refers to the species as planicollis in the title and carbonarius on the plate. Hopkins (s, p. 134) states 

 that L. carbonarius is evidently distinct from L. planicollis, and therefore Dugds's specimens are L. car- 

 bonarius. 



Journal of Agricultural Research, Vol. VI, No. 7 



Dept. of Agriculture, Washington, D. C. May 15, 1916 



dq K— 32 



(273) 



