1 62 PHYSIOLOGY OF THE INVERTEBRATA. 



another band, from S9.5-61.5, were faintly seen Tlie 



two chief bands and the absorption of th6 violet end were 

 also seen in the blood of a living larva by passing the light 

 through one of the claspers." 



Poulton has also examined the blood of the pupae of the 

 Pygmra Buc&phalus, SpJiinx Ligustri, Chmrocampa Mpenor, 

 Smerinthus Ocellatus, Smerinthus Tilice, Smerinthus Populi, 

 Dicranura Vinula, Papilio Machaon, EpJiyra Punctaria, and 

 the ova of Ennomos Angularia, S. Tilice, S. Ocellatus, and 

 Sphinx LigvMri. He has also made a comparison between 

 the spectra of the pigments contained in the blood of Lepi- 

 dopterous larv^ and pupse, and the spectra of unaltered plant 

 pigments (see Fig. 31). 



The spectrum of the green blood of the pupa of P. Bucephalus 

 is represented in Fig. 31, sp. 3. "The characteristic band 

 in the red ends sharply at 71, gradually at about 64.5, pass- 

 ing into a lesser absorption of the red, which is continuous 

 with the second band, extending from about 58-60.5, but 

 with very indistinct limits. When these appearances are 

 best seen, the violet end is completely absorbed to 52, dark- 

 ened to 52-5' 0^ opening the slit a little, the dimmed blue 

 comes though from 48-42. The band in the blue now sharply 

 ends at 52, gradually at 48. Diminishing the thickness of 

 the blood to 8 mm. (the previous thickness being 23.5 mm.) 

 produces nearly the same spectrum, the band in the red being 

 a little narrower, while the band at D cannot be detected. 

 On diminishing the thickness still further to i mm., another 

 band appears in the violet. The spectrum is as follows : 

 The characteristic band from 65-70 ; the chief band of the 

 blue end, 48-5 1 ; the second band of the blue end, 45-46.75 ; 

 the violet being absorbed at 41. The second band of the 

 blue end is much fainter than the first band, and it is not 

 seen in a thickness of 5 mm." 



Fig. 31, sp. 2, represents the spectrum of the fresh blood 

 of the pupa of Sphiiix Ligustri. The characteristic band 

 extends from 70 to 64.5, becoming gradually continuous with 



