ERUPTIONS PRODUCED BY FLEAS, BUGS, &c.
The common flea (Puler irritans) produces rose spots with a purplish point in the centre. When the surrounding redness fades the central spot remains still dark, and cannot be made to disappear even momentarily by pressure of the finger. Within two or three days it passes through the changes of colour common to any bruise and then disappears. In sensitive skins a kind of nettle-rash may be produced.
Bugs (Oiinex lectularia) hide in cracks of wood-work, bed-furniture, &c. They are much larger than fleas or lice, and are of a rusty brown colour.
They cause intense itching and large wheals by their bites, and an eruption like nettle-rash may be brought out, which is well-marked in the morning, and fades in the course of the day, to be again well-marked next morning.
The (Leptus autumnalis) em beds itself in the skin, and produces a pimply eruption, accompanied by itching, which in creases whenever the body grows warm, as after being in bed for some time at night.
Treatment. —The itching in any of these cases may be allayed by a lotion of percloride of mercury, 2 grains to the ounce of water. A stronger lotion of the same sort may be used to wash over cracks of wooden beds, &c., for the destruction of the insects. Great care must be exercised in its use, for it is very poisonous. The same end may be served by using a mix ture of 3 parts unpurified petroleum to 100 parts of water. Fumigating a house with sul phur also destroys bugs.
The harvest bug is a great peat in some country districts and in gardens, where many people dare not enjoy the luxury of gooseberry eating from the bushes, lest they be attacked by the insect. Rubbing the skin of the legs lightly with cedar-wood oil is an absolute pre , ventive in such cases.
Ringworm (Tina) occurs in three varieties, according as it attacks the scalp, the beard, or some other part of the body. In all cases it is due to the same cause, the presence of a vege table parasite, consisting of minute round bodies, and of thread-like structures formed of rows of rod-shaped bodies of a beaded appearance.
This is the growing fungus and its spores. To it the name trichophyton has been applied. Wherever ringworm occurs this is present be tween the layers of cells of the scarf-skin, in hairs and hair sheaths.
Ringworm of the body (Tinea circinata) is the name given to the disease when it occurs on the non-hairy parts of the body. It is most common on the face, neck, and trunk, and is found also on hands, arms, and wrists. It con sists of small circular patches slightly raised and of a rose colour, and covered with small branny scales. Usually round the margin is a ring of very small blisters. The spot is the seat of a tingling and itching sensation. It spreads round the margins, and as it spreads heals in the centre, so that a large red ring with a pale centre is formed. When a large ring has been formed it often becomes irregular. The disease may end of itself. On the other hand, it may spread and other rings may form on other parts because of the person scratching the diseased part, and carrying some of the fungus under finger-nails to some sound parts.
Ringworm of the scalp (Tinea toneurane) begins by small red patches like the ringworm of the body and spreads at the margins (Plate XXIV.). It involves the hairs, which become penetrated by the fungus, and are dull, dry, and twisted. They are easily pulled out, and be come very brittle, themselves breaking off near the skin and leaving projecting discoloured stumps. The affected patch becomes covered with a grayish-white powder. Inflammation may be produced and crusts formed. The hairs, if pulled out and examined, are easily seen to be very much thickened. In advanced cases of the disease the hair follicles may be destroyed and a bald patch be left when the disease has dis appeared. Several patches of the disease may exist, and by spreading unite, forming one large irregular patch.