132 THE BLUE BLOOD OF MOLLUSCA AND MOLLUSCOIDA. [BOOK I. 



To the green substance Lank ester applied the term Chlorocruorin, 

 and concluded that this body, like haemoglobin, was capable of existing 

 in two states of oxidation ; when oxygenized he proposed to designate 

 it oxy-chlorocruorin. Furthermore Lankester found that the action 

 of certain reagents upon chlorocruorin appeared to indicate that 

 when decomposed it yields products which have identical spectra to 

 those of certain haematin derivatives. 



ON THE BLUE BLOOD OF CERTAIN OF THE MOLLUSCA AND MOLLUSCOIDA. 



1. The blood of the mollusca has received considerable attention. 

 Usually the blood of animals belonging to this class presents a white 

 colour, but sometimes it is distinctly of a blueish tint. C. Schmidt 

 analysed the blood of the Pond-mussel (Anodonta cygnea) and found it to 

 be colourless and slightly alkaline. It deposited a pale fibrinous coagulum ; 

 it contained 0-854 p. c. of solid constituents, and of these there were 0-033 

 of a fibrin -like body, 0-565 of albumin, 0-189 of lime, 0-033 of sodium phos- 

 phate, sodium chloride, calcium sulphate, and 0-034 of calcium phosphate ! . 



2. The blood of the large shell-snail (Helix pomatia) was found by 

 Harless and von Bibra 2 to contain S'393 p. c. of organic and 6'12 p. c. of 

 mineral matters, there being 0'055 of oxide of copper in the latter. 



This blood acquired a blue colour on exposure to air which disappeared 

 under the influence of C0 2 . Alcohol precipitated a colourless coagulum and 

 ammonia removed the blue colour, which reappeared on neutralizing the 

 solution with hydrochloric acid. 



Harless and von Bibra stated that the blood of Helix pomatia 

 contained copper, but no iron, but v. Gorup-Besanez states that on having 

 these observations repeated under his direction, in addition to copper, iron 

 was also found in the ash 3 . 



3. Harless and von Bibra also investigated the blood of certain Cepha- 

 lopods (Loligo and Eledone) and Ascidians, which they likewise found to 

 contain copper but no iron. They assert that this blood possesses altogether 

 opposite colour properties to that of Helix pomatia, i.e. that it is blue 

 when free from oxygen but becomes colourless when shaken with air, again 

 being bleached when oxygen is passed through it. v. Gorup-Besanez con- 

 siders that this statement requires further proof before it can be accepted 4 . 



4. The whitish-blue blood of Limulus Cyclops was examined by A. 

 Genth 5 . A few seconds after this blood is shed a yellowish-white coagulum 

 separates from the liquid, which retains its blue colour. The latter is 

 destroyed by boiling and by putrefaction. Genth analysed the ash of the 

 blood of this creature and found it to contain in one case 0-081 p. c. of 

 oxide of iron, and 0'085 of cupric oxide; in another case only a trace of 

 iron, but 0*297 p.c. of metallic copper. 



1 C. Schmidt : see Lehmann's Physiological Chemistry, Vol. in., p. 256. 



2 Harless und von Bibra, Miiller's Archiv, 1847, pp. 148157. " Ueber das blaue 

 Blut einiger wirbellosen Thiere und dessen Kupfergehalt." 



3 Gorup-Besanez, Lehrbuch der physiologischen Chemie, p. 369. 



4 Gorup-Besanez, Op. cit. p. 370. 



6 " Ueber die Aschenbestandtheile des Blutes von Limulus Cyclops." Ann. d. Chem. 

 '-- Ptiarm., LXXXI. (1852), p. 68. 



