84 ZOOLOGY 



])y binding the leaves together and sucking the sap of the plant 

 or bj' destroj'ing the young seed. 



The mosquitoes, or Cuhcidffi/ are so well known that it is 

 hardly necessary to describe them. The larvas are aquatic. 



Fig. 89. — Plant galls produced by Hcmiptera and Diptera. 1. Pine-apple gall 

 on twigs ot the spruce fir produced by the spruce-gall Aphis {Chenncs ahrctis, 

 one of the Hcmiptera). 2. Covering gall on the petiole of the pyramidal 

 poplar {Popjdus pyramidalis), produced by Pemphigus liursan us. one of 

 the Hemiptcra. .3. Covering galls on an ash leaf {Fra.rinu.-i f.rcclsiur), pro- 

 duced by Diplosis hotularia (Diptera). 4. Covering gall on Pisfaria (Pistafla 

 leniiscus), produced hy Pcviphigus cornicularuis. 5. Solid galls on the corte.^ 

 ot Duvana longiJoH-a, produced by Cecidoses eremile (Hemiptcra). 6. Lon- 

 gitudinal section of one of these galls. 7. Capsule galls on the leaf of the 

 turkey oak (Qucrcus cerris. Hemiptcra). produced hy Crridoini/la cm-is. 



8. One of these galls cut through, with the operculimi still firmly attached. 



9. The same, with the operculum falling away ; 3. The remaining figures 

 natural size. From Kerner, " Pflanzen Leben." 



1 Cidcx w^as Pliny's name for fly. 



