332 
POPULAR SCIENCE REYIEW. 
its motion should turn in the same direction as before seems paradoxical, 
but maybe explained by the laws of currents. Further, the secondary 
couple once charged gives a current more powerful than that produced by 
the machine which it puts in motion, the difference of intensities continuing 
the motion. 
ZOOLOGY AND COMPARATIVE ANATOMY. 
On Hcemogldhin in the Animal Kingdom. — To the “ Proceedings of the 
Royal Society” (No. 140), Mr. E. Ray Lankester, B.A., has contributed a 
splendid paper on this subject in which he gathers together all that has 
been done on the Continent, and adds to this his own researches on the 
point, which are much vaster. In this way he has produced the best 
and most exhaustive memoir that has been written on this important sub- 
ject. The following is an historical account of what has been done on the 
question : “After Hoppe Seyler and Stokes had shown that the red colour- 
ing-matter of the blood of Vertebrata could be recognized by its peculiar 
absorption-spectrum, Kuhne discovered that the same colouring-matter, the 
oxygen-carrying properties of which were known from other researches, 
was diffused in the voluntary muscular tissue of mammals, and imparted to 
them their red tint. Rollett 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 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 spectroscopic analysis the existence 
of Haemoglobin in the blood of the mollusk Planorhis, in that of the larva 
of the insect Cheironomus^ in that of the Crustaceans Cheirocephalus and 
Daphnia, and in the vascular fluids of the marine Annelids Eunice^ Nereis^ 
Terehella, and others. I found also that in the Annelids of the family 
“ Chlor^miens ” of Audouin and Edwards, as well as in some species of 
Sabella, the Haemoglobin was replaced by a body having similar properties, 
giving a dark red colour to the vascular fluid when seen in sufficient thick- 
ness, and a bright green in thinner layers. This body gave a very sharply 
marked and characteristic pair of absorption-bands in the oxidized condi- 
tion, 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 difiering from those of Haemoglobin. By the action of 
cyanide of potassium, followed by that of a reducing agent (sulphide of 
ammonium), this body, to which the name Chlorocruorin was given, 
furnished two absorption-bands identical with those exhibited by Haemo- 
globin when similarly treated. Last year I found that the red colour of 
the pharyngeal muscles of the Gasteropods Lymnceus irndPaludina was due 
to the presence of Haemoglobin diffused in the muscular tissue ; and at the 
Meeting of the British Association at Edinburgh I demonstrated its occur- 
rence in the pharyngeal muscular mass of Littorina, where it is in sufficient 
quantity to give a very intense blood-red colour. The interest of this fact 
consists in this, that in no other part, not even in the blood of these 
mollusks, does Haemoo-lobin occur : hence the doubts which Brozeit had 
