STECJCTUEE AND BIOLOGY OF SCHIZONEUEA LANIGEEA. 697 
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EXPLANATIONS OF PLATES 38-42, 
Illustrating Mr. J. Davidson’s paper on The Structure and 
Biology of Schizoneura lanigera, Hausmaun or 
Woolly Aphis of the Apple Tree. — Part I : The Apterous 
Viviparous Female.” 
Reference Lettering. 
a. Antenna. « d. Antero-dorsal rod. ah. i-ix. Abdominal segments. 
a.f. Articulation of clypeus with epicranium. a. g. Abdominal ganglion. 
an. Anus. ap. Anal plate, a. s. 1-7. Abdominal spiracles, a. t. Anterior 
dorsal trachea, a. v. Antero-ventral rod. b. c. Buccal cavity, b. i. 
Body integument, h. ta. Basal joint of tarsus, c. Chitinous thickening 
at posterior end of buccal cavity, cd. Cylinder or “ Kolben ” of sahvai-y 
pump. c. i. Integumental lip over opening of comicle. cl. Claws, cn. 
Cornicle, c. o. Opening of comicle. cox. Coxa. cs. Commissme. c. t. 
Connective tissue, c. tr. Stout trachea connecting thoracic spiracles. 
cy. Cytoplasm, d. b. Dorsal tracheal branch, d. f. Dorsal wall of 
