PLATE IV. 
Tas. XIII. Back-swimmers: adults and nymphs. 
Tab XV. Nepa. 
TAB. XVI. Ranatra. 
Tas. XIV. Naucorid. The above are photographs of the plates in 
Frisch, an old text published in 1727. Among the first published illus- 
trations of water bugs. (Not the first, however.) 
Puoto. 1. The toad bug resting upon sand. 
PHOTO. 2. Ventral view of female Corixid. Note the peculiar beak 
and remarkable differentiation of the limbs. 
PuHoTo. 3. Notonecta undulata. Say. 
PHoto 4. Buenoa margaretacea. Bueno. 
PHoTo. 5. Female Corixid—Ramphocorixa acuminata. Uhl. 
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