ANATOMY AND GENERIC CHARACTERS OF SCORPIONS. 373 
means of injections, an exploration of the great veins of the Scorpions. My observations 
were made upon freshly-killed specimens of Androctonus funestus, which I obtained from 
North Africa for the purpose. I used as injecting material sometimes soluble Berlin 
blue, sometimes a mixture of wax, tallow, and turpentine coloured by vermilion. By 
introducing the injection at various points, especially into the venous sacs surrounding 
the lungs (by means of a very fine nozzle) I satisfied myself that there is no passage 
through the pericardio-ventral muscles to the pericardium. The chief veins leading 
from these dilatations of the ventral blood-sinus to the heart run up the sides of the 
body quite superficially, lying outside the longitudinal dorsal muscles between these and 
the integument. ‘They enter the pericardium at its dorso-lateral angles right and left 
(Pl. LXXXI. figs. 1 & 2, sus/). Deeper than the longitudinal dorsal muscles is a 
second series of veins parallel to the first; but these do not open into the pericardium. 
In a pale-coloured Androctonus, the position of the main venous trunks may be seen 
by transparency when they are injected either from the pericardium or from one of the 
circumpulmonary sinuses. Views of a specimen thus injected are given in Pl. LXXX. 
figs. 1, 2, 3. On the ventral surface (fig. 3), the injection shows at intervals near the 
mid-line, and the edge of the circumpulmonary sinuses are also seen. Internally it is 
found, on dissection, that the injection, besides occupying numerous large flattened 
spaces between the lobes of the gastric glands and the genital organs, is chiefly 
aggregated in two deep-lying latero-ventral longitudinal trunks which dilate around 
and enclose each in-pushed lung-book. Although the pericardium also is found to 
be full of the injection and the hollow pericardio-ventral muscles are half-filled (on 
their pulmonary side) with injection, yet no injection is found to have penetrated along 
the whole length of these muscles so as to reach through to the pericardium. , 
On the contrary, the veins connecting the pericardium and ventral longitudinal sinuses 
are seen when a lateral view of the specimen is taken (fig. 2) to be injected. Here we 
find a large vein (svs/) branching in the prosomatic carapace, returning some blood from 
the coxal glands and the limbs. In the first and second mesosomatic segments small veins 
(sus/1, sus/?) are seen bringing the blood from the genital and pectinigerous segments 
to the pericardium. In the third, fourth, fifth, and sixth mesosomatic segments these 
lateral veins are much larger and extend directly from the circumpulmonary venous 
sacs to the pericardium. They appear also to have wide anastomatic trunks running 
longitudinally between them. In the first metasomatic segment, the lateral veins 
have a strongly marked posterior direction, and do not reach the ventral surface. 
The arterial system of Scorpions (probably of Androctonus) was carefully described 
by Newport; but he was not able to give a decisive account of either the capillary or 
venous system, on account of the fact that his specimens were not living, but badly 
preserved in spirits. 
In Pl. LXXX. fig. 15, I have drawn a view from the inside of an actual dissection 
displaying the tergum and large vessels, pericardium and muscles of Androctonus 
