There are three varieties of the leech: the small jungle leech, the common leech and the stone leech.

The latter will frequently creep up the nostrils of a dog while he is drinking in a stream, and, unlike the other species, it does not drop off when satiated, but continues to live in the dog's nostril.

I have known a leech of this kind to have lived more than two months in the nose of one of my hounds; he was so high up that I could only see his tail occasionally when lie relaxed to his full length, and injections of salt and water had no effect on him.

Thus I could not relieve the dog till one day when the leech descended, and I observed the tail working in and out of the nostril; I then extracted him in the usual way with the finger and thumb and the tail of the coat.
I should be trespassing too much upon the province of the naturalist, and attempting more than I could accomplish, were I to enter into the details of the entomology of Ceylon; I have simply mentioned a few of those insects most common to the every-day observer, and I leave the description of the endless varieties of classes to those who make entomology a study.
It may no doubt appear very enticing to the lovers of such things, to hear of the gorgeous colors and prodigious size of butterflies, moths and beetles; the varieties of reptiles, the flying foxes, the gigantic crocodiles; the countless species of waterfowl, et hoc genus omne; but one very serious fact is apt to escape the observation of the general reader, that wherever insect and reptile life is most abundant, so sure is that locality full of malaria and disease.
Ceylon does not descend to second-class diseases: there is no such thing as influenza; whooping-cough, measles, scarlatina, etc., are rarely, if ever, heard of; we ring the changes upon four first-class ailments--four scourges, which alternately ascend to the throne of pestilence and annually reduce the circle of our friends--cholera, dysentery, small-pox and fever.

This year (1854) there has been some dispute as to the routine of succession; they have accordingly all raged at one time.
The cause of infection in disease has long been a subject of controversy among medical men, but there can be little doubt that, whatever is the origin of the disease, the same is the element of infection.