TOXINS AND ANTITOXINS 71 



much less toxic than ricin, producing gastro-enteritis, hemorrhages, 

 and swelling of lymph-nodes. Local applications led to an acute 

 conjunctivitis and in hairy regions to transitory loss of hair, both 

 of which may be protected against by immunization. Robert states 

 that in India and Ceylon cattle were immunized (by feeding beans) 

 against the effects of wounds by abrin-coated projectiles. Roemer 

 found that by repeated application to the conjunctival sac of one 

 eye, he could produce an immunity which first protected that eye 

 and, after further immunization, served to protect the opposite 

 untreated eye, in this later stage becoming a general immunity with 

 antiabrin in the serum. Abrin is also a hemagglutinating agent, 

 and can be distinguished from ricin by immunological experiment. 

 In many respects abrin and its immunity resemble ricin very closely. 



Crotin is derived from croton seed, croton tiglium, and is less 

 toxic than either ricin or abrin. According to Elfstrand, it agglu- 

 tinates the red blood-corpuscles of beef, sheep, swine, and frog; it 

 hemolyzes the cells of rabbit, cat, and crow, and has no effect on the 

 erythrocytes of man, dog, guinea-pig, rat, hen, goose, and pigeon. 

 Immune sera can be produced by the usual methods. Jacoby found 

 in Grubler's pepsin a body which he called pseudo-anticrotin, cap- 

 able of neutralizing the action of crotin on erythrocytes in vitro but 

 not in vivo, and he found the same substance in gastric and 

 intestinal mucosa. 



Curcin is produced from the seeds of jatropha curcus, and robin 

 from the leaves and bark of robinia pseudacacia. Immune sera can 

 be produced against both of these. 



Phasin is a name given by Landsteiner and Raubitschek to a 

 hemagglutinating substance found in the seeds of the bean, pea, 

 lentil, and vetsch. Antiagglutinins are found in normal serum and 

 may be increased experimentally, but this substance or group of 

 substances can hardly be regarded as belonging to the class of 

 toxins because of little or no toxic symptoms following injection. 



Pollen Proteins or Pollen Toxin. The modern studies of hay 

 fever and of asthma place this subject so clearly in the group of 

 anaphylactic phenomena that its consideration is deferred (see 

 page 233). 



ZOOTOXINS 



Introduction. The zootoxins include the poisonous elements 

 produced in animal life. They may be, and most frequently are, in 

 the form of excretions of special poison glands or are found in secre- 

 tions of other glands, in blood and in tissues. The most important 

 are the snake poisons, but there are also included the poisons of 

 spiders, scorpions, bees, centiped.es, tarantula, toads, poisonous fish, 

 duck-bill platypus, and the sera of various animals. 



The snake venoms differ somewhat in their action according to 

 family, the colubridae, including the cobra, Australian black snake, 

 and others ; the viperidae, including the European viper and Ameri- 



