PHYSIOLOGY OF THE INVERTEBh'ATA. 



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Fig. 31. — Spectra of the Blood of Lepidopterous Larv^ss and Pup^. 

 (After E. B. Poulton. ) 



Spectrum i.— The blood of the larva of P. Meticulosa (green variety) examined 



in a thiclcness of about .75 mm. by sunlight. The blood had been allowed 



to remain in an open capillary tube for about four days, and was then sealed 



up after it had evaporated to half its bulk. 

 Spectrum 2.— The fresh and unaltered blood of the pupa of 5. Ligustri, examined 



in a thickness of 35 mm. by sunlight. 

 Spectrum 3. — The fresh and unaltered blood of the pupa of P. Bucephalus, 



examined in a thickness of 23 mm. by sunlight. 

 Spectrum 4.— Two fresh calceolaria leaves, gently compressed, and examined by 



sunlight. 

 Spectrum 5. — Five ditto ditto. 

 Spectrum 6.— The fresh and unaltered blood of the pupa of S. Ligustri, 



examined in a, thickness of 3 mm. by illumination from the bright sky near 



the sun. 



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