A NATURALIST IN NICARAGUA. 93 



was removed as soon as possible, if the old abode was broken up. That 

 the leaves were not eaten was shown by the fact that the refuse in 

 many deserted chambers was composed entirely of their decayed frag- 

 ments, exhausted as a manure for the fungus, and left as food for larva3 

 of several species of beetles. Some leaves were evidently unsuited to 

 the purposes of the ants. Grass, if carried in, was directly brought 

 out again, and thrown away. The carriers of this were probably 

 young ants, and may have got a severe ear-wigging for their stupidity. 

 After all, then, do ants, like hosts of other animals, learn by experi- 

 ence, and is instinct, so called, sometimes at fault ? 



Bates describes the sand-wasps, on the banks of the Amazon, which, 

 on making a hole, carefully examine the locality before leaving it to 

 procure food, and Mr. Belt noticed similar actions in repeated instances. 

 They take the same precautions that a man would do, who wished to 

 return to the same spot. Frequently, after going a few rods, they will 

 return, fly around for an instant, and then dart away. On ode occa- 

 sion, a portion of a green caterpillar was carried away by a wasp, 

 which, on returning for the other portion, missed its mark on alight- 

 ing, and became quite lost, when it took wing again, made circles 

 around the spot, and again alighted, but in vain. This was repeated 

 half a dozen times, and the insect seemed to get angry, buzzing loudly, 

 when finally it found its prey. 



Butterflies of several kinds are described as abundant, but the 

 migration in enormous swarms of one or more species, which occurred 

 every year, is an interesting phenomenon. 



Flights of butterflies were thus described by Darwin in 1832 : 

 " When ofl" the shores of Northern Patagonia, we were surrounded by 

 vast numbers of butterflies, in bands or flocks of countless myriads, ex- 

 tending as far as the eye could range ; even with the aid of a telescope, 

 it was not possible to see a space free from butterflies." Mr. Belt had 

 seen immense migrating flocks in Brazil, journeying southeastward, 

 as were all those seen by him in Nicaragua. These were a brown- 

 tailed species [Tlmetes chiron)^ and there were no return-swarms, but 

 a continuous migration in one direction only. The gilded, day-flying 

 moth {Urania leilus), and a few yellow butterflies, were seen with the 

 migrating hosts. 



Birds, which are abundant at all seasons in the country, have a 

 habit of associating, possibly for safety, or, as Mr. Belt suggests, to 

 assist each other in hunting for food. Thus, flocks of hundreds, com- 

 prising a score of difierent species, are frequent, and, when present, the 

 trees seem alive with them. He could scarcely go abroad without 

 meeting them ; fly-catchers, woodpeckers, tanagers, creepers, trogons 

 of several species, all associating, apparently, on the most friendly 

 terms, for mutual help. 



The natives found about the country, as well as in the towns, repre- 

 sent an inferior type of civilization. They are, as a rule, excessively 



