PRACTICAL ENTOMOLOGY. 

 QIJISCALUS PURPUREUS.— C?-oa« Blackbird. 



443 



Date of capture 



KINDS OF FOOD. 



I. MOLLUSCA 



Univalve 



IL 



Insecta - - - 



Undetermined 



Larvas 



PnpjB 



Imago 



1. Lepidoptera (Larvae) 



Undetermined 



Noctuidoe — . 



2. Diptera.. 



Cecidomyiadse {Piiparia). 



3. Coleoptera 



Undetermined 



Larvie 



Images 



Scarabeida^ 



ElateridoD 



4. Hemiptera 



Nepidce 



Belostoma (Eggs). 



5. Neuroptera 



Undetermined 



LibellulidaD 



III. Crustacea 



Cray-fish. 



IV. Vegetation 



May. 



2C 



Percentage of each 



Element of 



Food. 



.02 

 .02 



.98 

 .34 



.28 



.06 

 .19 

 .19 



.01 

 .01 

 .42 

 .37 

 .32 

 .05 



.05 

 .02 

 .02 

 .02 



.98 

 .60 

 .44 

 .10 

 .06 

 .10 



".io 



.18 

 .14 

 .10 

 .04 



.04 

 .06 

 .06 

 .06 

 .04 

 .04 



.02 



.72 

 .07 



.11 

 .11 



,02 

 .01 



.01 



".39 

 .39 

 .39 

 .24 



'.24 



.27 

 .27 



.02 





.01 

 .01 



.89 

 .33 

 .24 

 .03 

 .04 

 .13 

 .10 

 .03 



.21 

 .17 

 .14 

 .03 



'.03 

 .15 

 .15 

 .15 

 .09 

 .01. 

 .08 



.09 

 .09 



.01 



ECONOMIC KELATIONS. 



Here again we see the necessity of a knowledge of food habits of dragon 

 flies, as also of the crayfish. The eggs of Hemiptera found so numerously 

 were in all probability those of Belostoma Americanum, a large brownish 

 bug inhabiting our fresh water lakes, rivers, and ponds; this insect is injurious 

 because of its habit of killing small fish by transfixing them on its spear- 

 like beak. The grass found was probably accidentally introduced. Taken as 

 a whole, the good done by young blackbirds, as indicated by the specimens 

 examined, far overbalances the slight injury probably due to the destruction 

 of beneficial insects. 



SirFFICIBNCY OF DATA. 



No one is better aware of the insufiBcieucy of the data here given for any 

 very general conclusions than myself. The difficulty of obtaining specimens, 

 the time required for each examination as well as the pressure of other duties 

 have rendered the examination of a greater number of specimens and species 

 impossible. The subject has been so little investigated in the past that the 



