PRACTICAL ENTOMOLOGY. 



445 



RANA HALECINA.— /SJjotterf Frog. 



ECONOMIC STATUS. 



Viewing tliese results from an economic standpoint, we observe that of tlie 

 87 per cent of insects and spiders which are eaten in July by the spotted frog, 

 at least 52 per cent are injurious, that about 26 per cent are of a doubtful 

 nature, and that about nine per cent, consisting of the undetermined carabid 

 beetles and spiders, are probably beneficial. But even this small percentage 

 is probably unfair to the frogs, as it gives all the undetermined Oarabidm the 

 credit of being beneficial. When we consider that all of these beetles which 

 could be determined were either of very slight benefit or none at all we may 

 well 'doubt whether the undetermined ones were any more beneficial. In the 

 present state of economic entomology we must class the spiders as beneficial, 

 although to what extent they are so is uncertain. The ten per cent of vegetable 

 matter consisting of dry grass, small pieces of wood, etcetera, accidentally 

 introduced, can not be considered as against the frog. 



