Comparative Studij of Chlorophjll. 



409 



Chelidonium majus, L. 



One leaf examined in gas-light showed — 



1. Dark band : X 686 [centre = X 672] - X 662. 



2. Paler band : from X 662-X 636-5. 



3. General absorption commencing in the blue end at 



X 503. 



JVpnpha-a alba, L. 



A young leaf examined in gas-light showed — 



1. Bark band : X 686 [centre 667] -X 661. 



2. A paler band : from X 661 - X 643-5. 



3. A very faint band, centre at X 604. 



4. An absorption with a very faint centre at X 576. 



Having thus briefly described the methods employed in 

 my investigation, and the results got with each plant sepa- 

 rately, I shall now endeavour, by comparing these, to form 

 a conclusion as to the absorption-spectrum of living chlo- 

 rophyll. I begin with the bands in the red end of the 

 spectrum. 



The First Absorption-Band of living chlorophyll extends 



m- 



Spirogyra from 



Ulva 



Trichomanes 



Asplenium 



X 678-X 662 



X 694-X 662 



X 694 - X 677 = one leaf. 



X 692 - X 662 = two leaves. 



X675 — X ? = four leaves. 



X 698 — X 655 = one leaf. 



X 676 — X 658 = two leaves. 



X 690 - X 662 = one leaf. 



X 686-X 652 = 



X 686-X 672 = 



X 686-X 653 = 



X 686-X 662 = 



X 686-X 661 = 



Stangeria 



Podocarpus 



Hedychium 



Pitcairnia 



Chelidonium 



Nymphsea 



The average is therefore X 686*69 — X 661-5 



The position of the first band I believe to be very approxi- 

 mately between X 686*6 and X 661*5, with its centre about 

 X 674-4, as a reference to the table on page 408 will show. 



