=Venomous snakes= named in order of virulence: 1. Coral snakes, _Elaps_, about seventeen red bands bordered with yellow and black (coloured figure 6) (fatal). 2. Rattlesnakes (very deadly). 3. Copperhead (may kill a small animal of the size of a dog). 4. Water moccasin (never fatal). 5. Ground rattler.—_Effects_: Pulse fast, breathing slow, blood tubes dilated, blood becomes stored in abdominal blood tubes, stupefaction and death from blood being withdrawn from brain. Always two punctures, the closer together the smaller the snake. _Remedies_: Ligature between wound and heart, lance wound and suck; inject into wound three drops of 1 per cent solution of chromic acid or potassium permanganate. Give strychnine, hypodermically, until strychnine symptoms (twitchings) appear. No one but a physician should give strychnine. Digitalin or caffein acts like strychnine; alcohol has opposite effect. [Illustration: FIG. 276.—“GLASS SNAKE,” a lizard without legs. ] [Illustration: FIG. 277.—SKULL OF ELAPS. See colored Fig. 5. ] [Illustration: FIG. 278.—SKULL OF LAMPROPELTIS. ] =Protective Coloration and Mimicry.=—When an animal imitates the colour or form of its _inanimate surroundings_ it is said to be _protectively coloured_ or formed. Give an instance of _protective Coloration_ or _form_ among lizards; butterflies; grasshoppers; amphibians; echinoderms. When an animal imitates the colour or the form of _another animal_ it is said to _mimic_ the animal. Mimicry usually enables an animal to deceive enemies into mistaking it for an animal which for some reason they avoid. The milkweed butterfly has a taste that is repulsive to birds. The viceroy butterfly is palatable to birds, but it is left untouched because of its close resemblance to the repulsive milkweed butterfly. The harlequin snake (_Elaps_) of the Gulf states is the most deadly snake of North America (Figs. 277, 278). It is very strikingly coloured with rings of scarlet, yellow, and black. This is an example of _warning_ coloration. The scarlet snake (_Lampropeltis_) has bands of scarlet, yellow, and black (coloured Fig. 6) of the same tints, and it is hardly distinguishable from the harlequin. The scarlet snake is said to _mimic_ the harlequin snake. It also imitates the quiet inoffensive habits of the harlequin snake, which fortunately does not strike except under the greatest provocation. The rattles of the less poisonous but deadly rattlesnake (Fig. 272) may be classed as an example of _warning sound_ which most animals are quick to heed and thus avoid encounters which might be destructive to either the snake or its enemy. [Illustration: COLOURED FIGURES 1, 2, 3.—CIRCULATION IN FISH, REPTILE, MAMMAL. In which is blood from heart all impure? Mixed? Both pure and impure? ] [Illustration: FIG. 4.—ANATOMY OF CARP. For description see Fig. 220, page 117. ] THE DEADLY HARLEQUIN SNAKE IS MIMICKED BY THE HARMLESS SCARLET SNAKE. [Illustration: