1916] Hyslop — Prothefehj in the Elatcrid Genus Melanotiis 3 



yellow band near tip; base of tarsi slightly lighter; coxae and trochanters yellowish 

 or pinkish. Thorax beneath pinkish; venter reddish. First segment of beak 

 brownish yellow, remainder blackish. 



Male, about 5 mm. in length; similar to female. 



PROTHETELY IN THE ELATERID GENUS MELANOTUS. 



By J. A. Hyslop, 

 Bureau of Entomology, Washington, D. C. 



Two papers on the abnormal phenomenon termed prothetely 

 appeared last year in Psyche. In one of these papers^ six biblio- 

 graphical references were given on the subject and in the other 

 paper- a seventh was added to this list. Dr. Adam Boving brought 

 another interesting paper on the same subject, published in 1914,' 

 to my attention, and in looking over the literature two more papers 

 were located. ^'-^ 



The present paper deals with a very striking case observed at the 

 United States Entomological Laboratory in Hagerstown. The 

 subject was Melanotus communis Gyll. 



On May 18, 1915, Mr. J. J. Davis sent the writer fifty-eight 

 living larvae of Melanotus communis Gyll., collected near Cincin- 

 nati, Ohio, with the note that they were found damaging corn on 

 river })ottom land. These larvte were shipped in salve boxes filled 

 with moist Sphagnum moss, and when received were isolated in 

 similar boxes partly filled with moi.st earth and fed seed corn. 

 The boxes were all placed in galvanized iron trays and the contents 

 examined, cast skins removed, soil moistened when necessary, and 

 new food supplied, weekly.^ 



Strickland^ suggested as an explanation of the phenomenon of 

 prothetely that it "is usually caused by keeping the larvae at an 

 abnormally high temperature. " The temperature to which this 

 particular larva was subjected could not have varied to any appre- 



1 Williams. F. X., 1914, Psyche, Vol. XXI, p. 126. 



2 Barber, H. S., 1914, Psyche, Vol. XXI, p. 190. 



3 Kemner, A., 1914, Ent. Tidsk. (Swedish), Vol. XXV, pt. 1-2, pp. 87-95. 

 < Tragardh, I., 1912, Fauna och Flora, pp. 245-255. 



^ Peyerimhoff, P. de, 1911, Bull. Soc. Ent. France, p. 327. 



8 The writer was ably assisted in this work by Messrs. H. L. Parker and W. E. Pennington of 

 the Station staff. 



■' Strickland, E. H., 1911, Biol. Bull., Vol. 21, pp. 313-327. 



