11 



habits had been less known. Instead of scattering- or becoming bewil- 

 dered -under the strange conditions they act from the first as though 

 they were thoroughly familiar with their surroundings. Many colo- 

 nies have been tested on a table isolated below by water. The insects 

 were allowed to climb out of their cages hj means of a ladder consist- 

 ing of a cotton leaf with the stem bent back. There was no hesitation 

 or preliminary exploration. The ants filed out at once and spread 

 themselves over the table. Weevils were often caught, stung, and 

 carried back to the cage within a minute or two after the release of 

 the ants from their captivity. 



All observations continue to confirm the previous report, that this 

 ant is a truly predaceous insect. Compared with the nervous haste 

 of many other species, its motions are slow and deliberate, and, like 

 the so-called praying mantis, it stands for long periods quite motion- 

 less, with its antenna? and mandibles extended, ready for something 

 to come that wa}^ and be caught. It seldoms attacks weevils or other 

 insects unless the} T are in motion and a weevil is generall\ T safe as long 

 as it keeps quite still. The ant's field of vision seems limited to less 

 than an inch. This, however, is adequate for practical purposes, since 

 the most convenient time for catching the weevil is when it is climbing 

 up the plant. In Guatemala a weevil placed on a leaf stem so as to 

 walk up and meet an ant was almost sure to be taken. In that coun- 

 try, however, weevils are seldom or never seen crawling about on the 

 cotton, perhaps because the ants have discouraged this habit; but Mr. 

 Hunter informs me that in Texas the weevils frequently 7- reach the 

 bolls by climbing up from the ground, and that they usually 7 pass 

 along the stems from one square or boll to another, so that the oppor- 

 tunities of the ants are excellent. 



That the ants know how to sting the weevils at the only two points 

 where their armor is vulnerable shows, of course, a highly specialized 

 instinct, and it is altogether likely that all individuals do not possess 

 it in an equal degree. Some colonies, too, attack the weevils much 

 more promptly and skillfully^ than others. As might naturally^ be 

 expected, hunger increases the eagerness and adroitness of the insects, 

 and it seems, too, that the members of the large colonies show more 

 ferocity than those of the small, as is known to be the case with the 

 honeys bee and many other social animals. The imported colonies 

 contain 'from twenty to one hundred and ten workers each, averaging 

 between forty and fifty. It may be that the smaller communities and 

 their queens would survive in captivity as long or longer than the 

 larger colonies, but if it should appear that they T are less able to forage 

 successfully the desired increase in numbers may be much slower, so 

 that the use of larger cages and the bringing of larger colonies may 

 prove desirable, should further importations of the ants be made 

 The rate of propagation of the keleps is likely to prove much slower 



