510 TRANSACTIONS LIVERPOOT, BIOLOGICAL SOCIETY. 
corpuscles of 15 » diameter (PI. VI, fig. 44), with rounded 
or slightly curved nuclei. After a lapse of several 
minutes, these corpuscles are seen—if the blood is placed 
in a watch-glass after withdrawal from the body—to 
congregate together in large clusters. 
(2) A lhquid medium, in which the above corpuscles 
float, containing :—(1) Mineral salts (including iron in 
small quantity, Girod); (2) slight traces of organic 
compounds; and (3) 9 per cent. of the substance 
Haemocyanin, an albuminous compound containing 
copper. According to Cuénot, it is the great quantity of 
copper present which gives the blue tinge to the blood. 
This darkens when exposed to air, because of the oxidation 
of the copper. ‘The blood of Eledone, like that of all 
Cephalopods, contains no fibrin. The analysis of the 
contents of the blood plasma has not been made for 
iy. cirrosa, but Frédéricq and Cuénot made it for Octopus | 
and Sepia respectively. Two glands have been suggested 
as the seat of origin of the blood corpuscles:— (1) The 
branchial gland (Joubin), and (2) the white body 
(Faussek). 
HEART. 
In Eledone the heart is situated just behind and to 
the right of the stomach (Pl. VI, fig. 42, V.). It is, 
however, rather ventral to this organ, but dorsal to, and 
therefore concealed by, the kidneys 
The heart is rather smaller than the stomach, and 
consists of three chambers, two auricles and a central 
ventricle, into which the auricles open laterally, one at 
each side. The two auricles are essentially the dilated 
and slightly muscular basal portions of the efferent 
branchial vessels, and may be defined as the portion of 
these vessels lying between the posterior end of the gill 
and the ventricle (fig. 42, au.). The auricles are 
symmetrical, but the thicker walled, more fleshy ventricle 
