390 Mr. C. A. Sclmnck. A Photographic Investigation 



say they are identical led Tschirch to the belief that there must 

 also exist a like resemblance in the violet and ultra-violet region of 

 the spectrum. Tschirch in his investigations* shows this to be the 

 case, and finds a band in phylloporphyrin (termed by him phyllo- 

 purpuric acid) in the same position as the band observed in haema- 

 toporphyrin, and this ' corresponding to the characteristic band 

 which has been shown to exist in the blood colouring matter 

 derivatives. But further on I will show that this particular 

 resemblance in these two derivatives is only partly correct, the 

 band in the phylloporphyrin I examined being double, though 

 occupying the same position as the single one of hagmatoporphyrin. 



Tschirch (in the same memoir) makes the further important dis- 

 covery that this band is not confined to phylloporphyrin alone, but 

 that it is distinctive of the chlorophyll derivatives generally, and 

 that it occupies (in the derivatives he observed) the same position 

 (varying between narrow limits) as that shown to exist in the blood 

 derivatives, and, like the blood band, the new chlorophyll band 

 shows much greater stability than any of the other bands, no 

 matter what chemical changes the derivatives have undergone. 



The chlorophyll derivatives investigated by Tschirch are phyllo- 

 purpuric acid (impure phylloporphyrin), phyllocyanic acid (phyllo- 

 cyanin), and its zinc, copper, and iron compounds, in all of which 

 he finds a single band corresponding in position with the band in 

 the haemoglobin derivatives, in the zinc and copper compounds 

 shifted slightly towards the red end of the spectrum, and he also 

 finds it indicated iu the living leaf, whilst in chrysophyll and 

 carotin he observes three bands situated between the solar lines 

 P and H and in identical positions. By the kind permission of Dr. 

 B. Schunck I have had access to his beautiful collection of chloro- 

 phyll derivatives, and have b*>en able to examine spectroscopically 

 in the pure state solutions of chrysophyll, carotin, chlorophyll, phyll- 

 oxanthin, phyllocyanin and its zinc and copper compounds, alka- 

 chlorophyll, phyllotaonin, ethyl-phyllotaonin, and phylloporphyrin, 

 and a specimen of hcematoporphyrin kindly sent me by Dr. L. March- 

 lewski. In all there appears a characteristic absorption between 

 the solar lines F and M, which confirms the statement of Tschirch 

 that the chlorophyll derivatives, like the haemoglobin derivatives, 

 give a very characteristic absorption in this region of the spectrum, 

 and considering the very near relationship which exists between 

 phylloporphyrin and hasmatoporphyrin, is further evidence of the 

 supposition that there exists something in common to both chloro- 

 phyll and haemoglobin, the two great colouring matters of biological 

 importance in the vegetable and animal kingdoms. 



* * Berichte der Deutschen Botaniachen Gresellscliaft,' vol. 14, Part 2, p. 76, 

 1896. 



