276 VENOMS 
Kobert! has made an experimental study of the venom of 
species of Latrodectus and ÆEpeira. That of Latrodectus erebus 
(the Karakurte of South Russia) is particularly toxic. 
If a dry extract of these spiders be prepared and injected into 
the veins of dogs or cats, it is found that a few milligrammes 
per kilogramme are sufficient to cause death, with phenomena of 
dyspnoea, convulsions, and progressive paralysis of respiration 
and the heart. Rabbits, rats, birds, frogs, and leeches are also 
sensitive to this poison, though the hedgehog is almost refractory, 
The young spiders, and even the eggs, are more toxic than the 
adults. 
Spider-venom is destroyed by heating for forty minutes at 
+ 70° C., and is precipitated by alcohol. When absorbed by 
ingestion it has no effect: it 1s haemolytic and coagulates blood. 
The study of arachnolysin by Ehrlich’s methods has been 
undertaken afresh by Hans Sachs,” who has shown that rat’s and 
_ rabbit’s blood are most rapidly dissolved. Twenty-eight milli- 
grammes of extract of Hpeira are capable of completely dissolving 
0-05 c.c. of blood. 
By immunising guinea-pigs and rabbits, Sachs succeeded in 
obtaining a strongly antitoxic serum, which entirely prevents the 
hemolysis of the sensitive red corpuscles. 
(b) Scorpionidea (Scorpions). 
The poison-apparatus of the scorpion is constituted by the last 
abdominal segment (telson), which is swollen and globular, and 
terminated by a hard, curved spine, with a very sharp point, near 
which can be distinguished, under the lens, two small oval orifices 
by which the poison is enabled to escape (fig. 97). 
The poison-glands are two in number, symmetrically placed in 
'“ Beitriige zur Kenntniss der Giftspinnen.” Stuttgart, 1901. 
24 Zur Kenntniss des Kreuzspinnengiftes,” Hofm. Beitrdge, ii., p. 125, 1902. 
2 “ D ? J ? 
