] 872.] Mr. E. Ray Lankester on Hcemoglobin. 



71 



tissues and its presence in others, with the accompanying conditions and 

 activities belonging to the particular organisms, to arrive at some data 

 bearing upon its physiological significance. Such a comparative method 

 has already yielded results as to the activities of many organs and tissues, 

 and is in all probability destined in the future, when applied to the more 

 minute problems of the functions of structures and tissue-components, 

 to give new impulse to the science of physiology. 



Before communicating some newly observed facts with regard to the 

 occurrence of Haemoglobin in animal organisms, I may briefly state what 

 is the present condition of the subject. 



After Hoppe Seyler* and Stokes t had shown that the red colouring- 

 matter of the blood of Yertebrata could be recognized by its peculiar 

 absorption-spectrum, KuhneJ discovered that the same colouring-matter, 

 the oxygen-carrying properties of which were known from other re- 

 searches, was diffused in the voluntary muscular tissue of mammals, and 

 imparted to them their red tint. Eollett§ then obtained from the red 

 vascular fluid of the earthworm crystals which were identical with those 

 of Haemoglobin, and Nawrocki|| at the same time as myself 1[ confirmed 

 the supposition that Haemoglobin is the cause of the red coloration of 

 the blood of Lumbricus, by careful spectroscopic observation of the fluid 

 and the derivatives yielded by it (Haematin). I also established by spec- 

 troscopic analysis** the existence of Haemoglobin in the blood of the 

 mollusk Planorbis, in that of the larva of the insect Cheironomus, in that 

 of the Crustaceans Oheirocephalus and Daphnia, and in the vascular fluids 

 of the marine Annelids Eunice, Nereis, Terebella, and others. I found 

 also that in the Annelids of the family " Chloremiens " of Audouin and 

 Edwards, as well as in some species of Sabella, the Haemoglobin was re- 

 placed by a body having similar properties, giving a dark red colour to 

 the vascular fluid when seen in sufficient thickness, and a bright green in 

 thinner layers. This body gave a very sharply marked and characteristic 

 pair of absorption-bands in the oxidized condition, which were changed to 

 a single one in the reduced condition, as in the case of Haemoglobin, the 

 bands, however, having a relative intensity and a position altogether 

 differing from those of Haemoglobin. By the action of cyanide of potas- 



* Hoppe Seyler, "Ueber die chemischen u. optischen Eigenschaften des Blut- 

 farbstoffs," Archiv f. pathol. Anat. u. Physiol. 1862, Bd. xxiii. 



t Stokes, " On the Reduction and Oxidation of the Colouring-matter of the Blood," 

 Proc. Royal Society, 1864. 



% Kuhne, " Ueber den Farbstoff der Muskeln," Archiv f. Pathol. Anat. u. Physiol. 

 Bd. xxxiii. 



§ Rollett, " Zur Kenntniss der Verbreitung des Hamatins," Sitzungsber. d. k. Ak. d. 

 Wiss. z. Wien, Bd. xliv. 



|| Nawrocki, Centralblatt fur die medic. Wissenschaften, 1867, p. 196. 



^[ Lankester, " Observations with the Spectroscope," Journal of Anatomy and Phy- 

 siology, 1867, p. 114. 



** " Spectroscopic examination of certain Animal Substances," ibid. 1869, p. 1 19. 



