STRYCHNINE AS FOOD OF AR^EOZERUS FASCIC- 

 ULARIS DE GEER. 



By Robert E. Brown, S.J., 

 Manila, P. I. 



The weevil, Araocerus fascicularis, is well known in all parts of the 

 world on account of its cosmopolitan habits. It feeds on all kinds of 

 seeds and nuts, but one of the strangest which it has been known to eat 

 is the St. Ignatius' bean, Strychninos ignatii Berg. This plant grows wild 

 in many parts of the Philippines, but is especially plentiful in the Island 

 of Samar, where the fruit is called by the natives pepita-sa-catbalongan 

 and pepita de San Ignacio. The bean is exceedingly poisonous, though 

 it is used by the natives as a remedy for certain diseases, and it is not 

 uncommon, as a consequence, that people die from an overdose. A 

 quantitative analysis of the bean gave as a result 1% per cent, strych- 

 nine and y 2 per cent, brucine. 



Strychnine is one of the deadliest poisons known, yet this little 

 beetle not only feeds on it, but actually breeds in the cavities which it 

 has bored in the seed. In the Observatory Museum there was a bottle 

 containing some ten Ignatius' beans and it was noticed that a male 

 and female A. fascicularis had been enclosed with them. The insects 

 seemed to be in good health and they began gnawing the beans with- 

 out any evil effects. Wishing to see if the weevil could live on such 

 deadly poison, the bottle was sealed and set aside and in about six 

 months, when examined, it was found that ten adult insects were en- 

 joying themselves within. They were taken out and the beans treated 

 with bisulphide of carbon to kill any eggs that might have been de- 

 posited in them by the weevils. Two males and two females were 

 then replaced in the bottle with the beans and the stopper sealed. In 

 little more than a week they all died, but in two months young larvae 

 could be seen in the cavities of the beans and they all grew to maturity, 

 Since that time more than four generations of A. fascicularis have 

 been bred and no other food but the Ignatius' beans was given them. 



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