AND OTHER INJURIOUS INSECTS OF IQO/ AND I908. IQI 



pointing downwards over the genital opening. This armature helps 

 to hold the young after they are born until they get their legs free. 



The Genital Plate: The genital plate belongs to the eighth 

 abdominal segment, and is situated just ventral to the genital open- 

 ing. It is semi-circular in shape when seen from the ventral side, with 

 the circumference pointing posteriorly projecting somewhat beyond 

 the genital opening. There is usually a row of hairs in a semi-circle 

 around the rim, and sometimes others not in rows anterior to these. 



Bibliography. 



Buckton George Boulder: ^lonograph of British Aphides, Ray So- 

 ciety, London, 1876. 



Cornu, M. Maxime: Etudes sur le Phylloxera vastatrix. Memoires A. 

 L. Academic Des Sciences de L'Institute de France, Tome XXVI. 



Flogel, J. H. L. : Monographic der Johannisbeeren Blattlaus, Aphis 

 ribis L. 



Heymons, Dr. Richard: Beitrage zur ^Morphologic und Entwickkmgs- 

 geschichte der Rhynchoten. Halle, 1899. 



Kaltenbach, J. H.: Monographic der Familien der Pflanzenlause 

 Aachen, 1872. 



Oestlund. O. W., Aphididae of Minnesota, Geological and Natural His- 

 tory Survey of Minnesota, 1887. 



Oestlund, O. W.: Antennal Sense Organs of the Aphididae, Bulletin of 

 the Minnesota Academy of Sciences. Vol. IV. No. 2. 



Sanborn, Charles Emerson: Kansas Aphididae, Kansas University 

 Science Bulletin, Vol. III. 



Thomas, Cyrus: Eighth Report of the State Entomologist on the 

 Noxious and beneficial insects of the State of Illinois. 



Witlaczil: Zur Anatomic der Aphiden, 1882: Ztschr. f. w. Zool. 38 

 1882. 



