444 Hev. II. C. McCook on the Architecture and 
plished for a long time ; but evidently the whole mass of 
refuse is thus loosened. Then conies the final burst, with 
soldiers, majors, and minors in the lead, who rush out bearing 
up before them the rubbish, which flies here and there, and 
in a few moments is cleared away from the gallery, and spread 
around the margin of the gate. These chips are evidently 
gathered together for this purpose and are among the 
“ treasures ” of the ants, being kept near by for this use. 
The pieces were easily identified as being thus used several 
days in succession. 
The above observation points out at least the use found for 
the extremely small forms peculiar to this species. At least 
ten distinct castes (forms or sizes) were exhibited to the 
Academy. They vary as follows, the measurements being in 
sixteenths of an inch, viz. $ , 14 ; , H ; soldier 7 ; worker 
major 6, minor 5; and the remaining castes in the proportion 
3^, 3, 2^, 2, 11, 1. A more careful comparison may possibly 
reduce this series one or two; but the result as above will 
probably stand. 
The gates first opened are the first closed, and those last 
opened are the last closed. 
3. Leaf-cutting Tiahit .—The whole process of cutting and 
carrying leaves from trees and shrubs was observed at 
Camp Wright and at a vegetable-garden near Austin. In 
order better to see the mode of cutting, small tender branches 
of live-oak were thrust into the mound near the gates. These 
were soon covered with ants; and as the lantern could thus be 
used conveniently, the operations of the cutters were com¬ 
pletely in view. The cutter grasps the leaf with outspread 
feet, and makes an incision at the edge by a scissor-like 
motion of her sickle-shaped toothed mandibles. She gradually 
revolves, steadily cutting as she does so, her mandibles thus 
describing a circle, or the greater portion thereof. The feet 
turn with the head. The cut is a clean one, quite though the 
leaf. The cutter will sometimes drop with the excision to the 
ground, sometimes retire when the section has dropped, some¬ 
times (it is inferred) seize the section and carry it down the 
tree. A division of labour was apparent. At the foot of one 
tree was a pile of cut leaves, to which clippings were con¬ 
tinually being added by droppings from above. Carriers on 
the ground took these up and bore them to the nest. The 
loading of the cuttings is thus: the piece is seized by the 
curved mandibles ; the head is elevated ; the piece is thrown 
back by a quick motion, seeming to be lodged on the head 
within the deep furrow that runs along the entire median line 
of the head (except the clypeus), and supported between pro- 
