144 
ZOOLOGY. 
swellings with itching are the consequence ; hut I found that 
after some time we became less sensitive to them, and the 
swellings were not so large. There were places where they were 
really dreadful; innumerable quantities of them attack the ex¬ 
plorer, and there is no way to protect himself. I made the 
observation that in the tents, during rain and shortly after rain¬ 
fall, they were the most savage. Often then we were enveloped 
with clouds of them, and no part of the body was safe. Those of 
my poor companions whose clothes were torn, suffered of course 
much more than the others. Although their abdomen is narrow 
and elongated, I could not but admire how they expanded and 
became quite round during the process of sucking, and instead of 
a blackish blue colour they became transparent and red, often 
gorging themselves till they were unable to fly. 
It seems that they are destined in the economy of nature to 
destroy putrid vegetable matter. Often I saw large quantities of 
kelp lying on the sea-shore, and arrived at a certain state of 
putrefaction, totally covered with them. As soon as it becomes 
dark they disappear, and the explorer can enjoy some rest. Their 
greatest foes are clearings and cultivations, and it is wonderful to 
observe how soon they disappear before the work of men. The 
Maori pah at the Grey, for instance, was in former years so in¬ 
fested by them, that the natives, in order to save themselves, had 
to build low huts with fires at the two only openings, sitting thus 
in the smoke; but since they began to cultivate a good portion 
of the land with potatoes and wheat, the sandflies have almost 
entirely deserted the pah. They cannot stand the cold, and I 
never found any in shady places in cold winter days. I observed 
them as high as an altitude of 2,500 feet, but never higher. 
Another unwelcome guest belonging to the same order is the 
mosquito (Culex) ; but it was fortunately of very local occurrence, 
and we travelled often for many miles without any sign of them. 
I know, in fact, only three spots where they occurred in any 
troublesome quantity. One was a deep gully of Mount Francis, 
near the Matakitaki plains, and the others were in gullies of the 
Maruia, but although we camped very often in quite similar 
places, we were never molested. It is true that the natives state 
that the mosquito is not indigenous to blew Zealand, and that it 
has been introduced by the Europeans ; but still it will be very 
difficult to explain how these diptera should be found in the 
country traversed by me only at a few isolated spots, and far in¬ 
land, and then in such large masses. 
The blue-bottle fly (Larcophaga loemica) is another insect which 
occurs over the whole country, its presence being quickly made 
known by its intolerable noise. I met with it on the summits of 
the highest mountains which I ascended. It is suited for every 
degree of temperature, for I found some of them on the summit 
of Papahaua, flying over the snow before the sun had risen, and 
