rjQ On Brazil Kitchen Middens, Habits of Ants etc. 



Some time ago I sent to Germany for publication a note on the relation 

 between our Imbauba trees (Cecropia) and the ants which inhabit their hollow 

 stem. As there may be some delay in publishing, I will give you a short abstract. 

 Mr. Belt has already stated that the ants farm scale-insects in the cells of the 

 Imbauba stem, and he believes that their presence must be beneficial. This is 

 no doubt the case; for they protect the young leaves against the leaf-cutting 

 ants (Oecodoma). Now there is a wonderful contrivance by which, as in the case 

 of the "bull's-horn acacia", the attendance of the ants at the right time and place 

 is secured. At the base of each petiole there is a large flat cushion, consisting 

 of most densely-crowded hairs, and within this cushion a large number of small 

 white pear-like or club-shaped bodies (specimens inclosed) are successively developed, 

 which, when ripe, emerge at the surface of the cushion, like asparagus on a bed, 

 and are then greedily gathered by the ants and carried away to the nest. The 

 object of the dense hair-cushion appears to be (i) to secure to the young club- 

 shaped bodies the moisture necessary for their development; and (2) to prevent 

 the ants from gathering the unripe bodies. In most cases it is by honey-secreting 

 glands that the protecting ants are attracted ; now Mr. Belt observed ("Nicaragua", 

 p. 225) that the honey-glands on the calyx and young leaves of a Passion-flow T er 

 were less attractive to the ants than were the scale-insects living on the stems; 

 this would most likely be the case with the Imbauba, and it is probable that the 

 use of the little pear-shaped bodies is to form an attraction stronger than that 

 of the scale-insects, and thus to secure the attendance of the protective ants on the 

 young leaves. As far as I could make out, the club-shaped bodies consist mainly 

 of an albuminous substance. The ant colonies are founded by fertilised females, 

 which may be found frequently in the cells of young Imbauba plants. Each 

 internode has on the outside, near its upper end, a small pit where the wall of 

 the cell is much thinner than anywhere else, and where the female makes a hole 

 by which she enters. Soon after this the hole is completely shut again by a 

 luxuriant excrescence from its margins, and so it remains until about a dozen 

 workers have developed from the eggs of the female, when the hole is opened 

 anew from within by these workers. It would appear that the female ants, living 

 in cells closed all around, must be protected against any enemy ; but notwithstand- 

 ing a rather large number of them are devoured by the grub of a parasitic wasp 

 belonging tho the Chalcididae; Mr. Westwood has observed that the pupae of the 

 Chalcididse exhibit a much nearer approach to the obtected pupae of the Lepid- 

 optera than is made by any other Hymenoptera ("Introd. to the Modern Classif. 

 of Insects," Part XI., p. 162). Now the pupa of the parasite of the Imbauba ant 

 is suspended on the wall of the cell by its posterior extremity just like the chrysalis 

 of a butterfly. 



I hope you will have received a paper on .^Eglea, a curious Decapod inhabiting 

 the mountain rivulets of our Serra do Mar. Lately I obtained a large number of 

 specimens of this ^glea, and among them a female with eggs in an advanced 

 state of development. Thus I was enabled to satisfy myself that, like so many 

 fresh-water and terrestrial animals, the marine allies of which undergo a trans- 

 formation, our ./Eglea does not experience any metamorphosis. 



Itajahy, St. Catharina, Brazil, Dec. 25, 1875. 



