268 



COLEOPTERA 



life-histories appear to he singularly varied ; but unfortunately 

 the}' are incompletely known. The larvae of some of the 

 Mordellids have been found in the stems of plants, and 

 derive their nutriment therefrom. This is said by Schwarz 

 to be undoubtedly the case with JlordcIIistcna floridcnsis. 

 Coquillett has found the larvae of M. jntMulata in plant -stems 

 under circumstances that render it highly probable that they 

 were feeding on a Lepidopterous larva contained in the stems ; 

 and Osborn found a similar larva that was pretty certainly a 

 Jfonlcllistcna, and fed voraciously on Dipterous larvae in the 

 stems of a plant. The little that is known as to the meta- 



FlG. 139.— MnnieUi- 

 steim Jlorideiisis. 

 America. (After 

 Eiley.) A, Larva; 

 B, pupa ; C, imago ; 

 D, oiitline of de- 

 tached head of im- 

 ago of JI. picmila, 

 to show the ueck. 



morphoses of Mordella and Anaspis shows that they live in old 

 wood, but does not make clear the nature of their food. 



Although it has been ascertained that the Ehipiphorides 

 exhibit instances of remarkable metamorphosis, their life- 

 histories are still very imperfectly known. Dr. Chapman has 

 ascertained some particulars as to Metoecus paradoxus, which has 

 long been known to prey in the larval state on the larvae of the 

 common social wasps.^ The eggs are apparently not deposited in 

 the nests of the wasps, but in old wood. The young larva is a 

 triungulin, similar to that of the Cantharidae, we shall sub- 

 secjuently describe. It is not known how it makes its way to 

 the wasps' nests, but it is possible that when a wasp visits some 

 old wood haunted by these larvae, some of them may attach 

 themselves to it and be carried to the wasps' nests. When 



^ Ann. Xat. Hist. (4) vi. 1870, p. 314 ; and Eiit. 3fag. xxrii. 1891, p. 18. 



