101 



NOTES ON THE BIOLOGY OF NECROBIA RUFI- 

 COLLI S. FABR. [COLEOPTERA, CLERIDAE.] 



By HUGH SCOTT, M.A., Sc.D. (Cantab.). 

 {Ctiralor in Entomologi/, University of Cambridge.) 



(With 2 Text-figures.) 



So much has been written about the subject of this paper that an 

 apology for bringing the matter up again seems necessary. I had, how- 

 ever, opportunity to observe the insect in numbers, and can place 

 on record some observations which are not mere repetition of any 

 hitherto published. During 1917 and 1918, being attached as entomo- 

 logist to the Hygiene Department, Royal Army Medical College, I 

 worked in the entomological laboratory of the Imperial College of Science, 

 South Kensington, and the observations herein recorded were made in 

 the intervals of routine work. A large room was given up to the breeding 

 of Musca domestica for experimental purposes : it was heated by radiators 

 and bunsen burners, and a constant succession of generations of flies 

 was maintained summer and winter alike. This fly-culture had been 

 started late in 1915 (long before my advent at the laboratory) and was 

 kept going continuously till late in 1917. The maggots were fed on a 

 mixture of brown bread, casein and banana, or, late in 1917, of bran, 

 casein and beetroot. The ingredients were thoroughly pounded and 

 mixed, and moistened masses of the mixture were placed in large shallow 

 vessels. The food was surrounded by sawdust in which the full-fed 

 maggots could pupate. As fresh food was added, the lower part of the 

 vessels became full of a mass of debris of old food, sawdust, and countless 

 empty puparia from which flies had emerged. It was in this dark- 

 coloured detritus that the Necrobia-lsuvsie lived. They kept below the 

 surface and were not seen unless the debris was turned over. Other 

 denizens of this debris were one or more kinds of Dermestes and the moth 

 Tinea pallescenfelki, Stainton. A bug, Lyctocoris campestris, Fabr. 

 ( = domesticus, D. and S.; Anthocoridae), was also present, though only 

 very few of this were found. Occasionally Fannia, Muscina stahulans, 

 Drosophila sp., and a minute Borborid fly^ also bred in the dishes. Other 



' Limosinu miniitissima, Zett. (determined by Mr J. E. Collin). 



