448 



Dr. E. Schunck. 



18. v. Witticli : ' Experimenta quaedam ad Halleri doctrinam de musculorum 

 irritabilitate probandam instituta.' Konigsberg, 1857, and ' Yircbow, Arcbiv,' 

 vol. 13, 1858, p. 421. In these papers, with, the discovery of the excitation of muscle 

 by distilled water, appears without doubt the first fact which overthrew the old 

 theory of the equal irritability of muscle and nerve. 



19. E. du Bois-E-eymond : ' Gresammelte Abhandlungen zur allgemeinen Muskel- 

 und Nervenphysiologie ;' vol. 2, p. 700. 



20. Kuhne : 1 Verhandlungen des Naturhist.-medicinischen Yereins zu Heidel- 

 berg ; ' Neue Eolge, vol. 4, pp. 4, 5. 



21. G-. Eetzius : 1 Biologische Untersuchungen,' 1881. 



A. Eollett : " Untersuchungen iiber den Bau der quergestreiften Muskelfaser." 

 ' Wien, Akad. Denkschr.,' vol. 49, 1885. 



22. 'Dr. H. Gr. Bronn's Classen und Ordnungen des Thierreiches, neu bearbeitet 

 von O. Butschli.' Leipzig und Heidelberg, 1888, vol. 1, p. 1298. 



23. Kuhne : " Neue Untersuchungen iiber motorische Nervenendigung." 

 ' Zeitschr. Biol.,' vol. 23, pp. 88-95. 



24. A. van Gehuchten : " Etude sur la structure intime de la cellule musculaire 

 striee." ' La Cellule,' vol. 2, p. 289. 



25. E. Hering : ' Sitzber. der k. Akad. zu Wien,' vol. 85, Abth. 3, 1882, p. 237. 



26. Kuhne : " Secundare Erree ung vom Muskel zum Muskel." 1 Zeitschr. Biol.,' 

 vol. 24, p. 383. 



The drawings, figs. 1, 2, 3, 5, 8 are taken from the papers of Dr. K. Mays : 

 " Histophysiologische Untersuchungen iiber die Yerbreitung der Herven in den 

 Muskeln" ('Zeitschr. Biol.,' vol. 20, p. 449), and " Ueber INervenfasertheilungen in 

 den Nervenstammen der Eroschmuskeln " (' Zeitschr. Biol.,' vol. 22, p. 354) ; 

 figs. 9 — 13, from the author's work in 'Zeitschr. Biol.,' vol. 23, pp. 1 — 148, 

 Plates A— Q. 



" Contributions to the Chemistry of Chlorophyll. No. III." By 

 Edward Schunck, F.R.S. Received June 19,— Read June 

 21, 1888. 



Products of the Action of Alkalis on Phyllocyanin. — In the first part 

 of this memoir I gave a general account of the action of alkalis on 

 phyllocyanin (' Proceedings,' vol. 39, p. 355). I shall now proceed to 

 give the results obtained on further examining the products due to 

 this action. The description of the products appearing in the first 

 stage of the process of change induced by alkalis forms the subject of 

 the present communication. 



The great trouble involved in preparing any considerable quantity 

 of phyllocyanin in a state of purity made it desirable to find out a 

 method, if possible, of obtaining the products of the action of alkali 

 directly from chlorophyll itself. The object in view was attained by 

 acting on chlorophyll first with alkali and then with acid, thus 

 reversing the process previously adopted and at the same time 

 leading to the discovery of several new and interesting compounds, 

 the formation of which had not been anticipated, 



