274 THE BLOOD. 



When the haemoglobin is separated from the so-called stroma by a 

 sufficiently strong dilution with water the stroma is found in the solution 

 in a swollen condition. By the action of carbon dioxide, by the careful 

 addition of acids, acid salts, tincture of iodine, or certain other bodies, 

 this residue, rich in proteins, condenses, and in many cases the form of 

 the blood-corpuscles may be again obtained. This residue, the so- 

 called ghosts or stromata of the blood-corpuscles, can also be directly 

 colored in dilute blood by methyl violet and in this way detected, and 

 attempts have been made to isolate it for chemical investigation. In 

 the following pages we mean by the name stroma only that residue which 

 remains after the removal of haemoglobin and other bodies soluble in 

 water. 



To isolate the stromata from the blood-corpuscles, they are washed 

 first by diluting the blood with 10-20 vols. of a 1-2 per cent common 

 salt solution and then separating the mixture by centrifugal force or 

 by allowing it to stand at a low temperature. This is repeated a few 

 times until the blood-corpuscles are freed from serum. These purified 

 blood-corpuscles are, according to WOOLDRIDGE, mixed with 5-6 vols. 

 of water and then a little ether is added until complete solution is obtained. 

 The leucocytes gradually settle to the bottom, a movement which may 

 be accelerated by centrifugal force, and the liquid which separates there- 

 from is very carefully treated with a 1-per cent solution of KHS04 until 

 it is about as dense as the original blood. The separated stromata are 

 collected on a filter and quickly washed. PASCUcci, 1 on the contrary, 

 treats the mass of corpuscles with 15-20 vols. of a one-fifth saturated 

 ammonium-sulphate solution, allows the corpuscles to settle, siphons 

 off the fluid, repeatedly centrifuges, allows the residue to dry quickly 

 (on porcelain plates) at the ordinary temperature, and then washes 

 with water until the blood-pigments and the other soluble bodies are 

 dissolved out. 



WOOLDRIDGE found as constituents of the stromata lecithin, choles- 

 terin, nucleoalbumin, and a globulin which, according to HALLIBURTON, 

 is pr&bably a nucleoproteid which he calls cell-globulin. No nuclein 

 substances or seralbumin or proteoses could be detected by HALLIBUR- 

 TON and FRIEND. According to PASCUCCI, the stromata (from horse- 

 blood) consists of one-third cholesterin and lecithin (besides a little 

 cerebroside), and two-thirds protein substances and mineral bodies. 

 The nucleated red blood-corpuscles of the bird contain, according to 

 PL6sz and HoppE-SEYLER, 2 a protein (nucleoprotein) which swells to a 

 slimy mass in a 10-per cent common salt solution, and which seems to 



1 Hofmeister's Beitrage, 6. 



2 Wooldridge, Arch. f. (Anat. u.) Physiol., 1881, 387; Halliburton and Friend, 

 Journal of Physiol., 10; Halliburton, ibid., 18; P16sz, Hoppe-Seyler's Med. chem. 

 Untereuch., 510. 



