Tiger-Beetles and Butterflies 229 
ing shrubs and low trees, proving that all the land had at one 
time been cropped, and this was further shown by the old 
lines of pinuela fences and ditches that were seen here and 
there amongst the brushwood. As we got further south the 
alluvial flats in the valleys increased in size and fertility, and 
the cultivated fields were enclosed with permanent fences. 
On some of the ranges we crossed, the rocks were amygda- 
loidal, containing nests of a white zeolite, the fractured 
planes of which littered like gems on the pathway. 
Eight leagues from Matagalpa we reached the small town 
of Tierrabona, where, as the name implies, the land is very 
good. Every house had an enclosure around it, planted 
with maize and beans: and though it was evident that the 
Jand was cropped year after year, it still seemed to bear well. 
We stopped at a small brook just outside the town, and ate 
some provisions we had brought from Matagalpa. Some 
speckled tiger-beetles ran about the dusty road, and on wet 
muddy places near the stream groups of butterflies collected 
to suck the moisture. Amongst them were some fine 
swallow-tails (Papilio), quivering their wings as they drank, 
and lovely blue hair-streaks (Thecle). The latter, when they 
alight, rub their wings together, moving their curious tail- 
like appendages up and down. Great dragon- flies hawked 
after flies; while on the surface of still pools “ whirligigs ” 
(Gyrinid@) wheeled about in mazy gyrations, just as they : are 
seen to do at home. 
Savannahs, sparingly timbered, were next crossed; then 
we reached one of those level plains, with black soil and blocks 
of porous trachyte lying on the surface, which are swamps in 
the rainy season, and have for vegetation sedgy grasses and 
scattered jicara trees, cactuses and thorny acacias. Up to 
the time we passed, there had been no rain in these parts, 
and the plain was dry and bare, with great cracks in the 
black soil. The grass had not sprung up, not a breath of 
air was stirring, and the heated air quivered over the parched 
ground, forming in the distance an imperfect mirage. 
Directly overhead the noonday sun hung hot in the hazy 
sky. As we moodily toiled over the plain, my attention was 
arrested by a dust whirlwind that suddenly sprang up about 
fifty yards to our left. The few dry leaves on the ground 
began to whirl round and round, and to ascend. In a 
