The Chihuahua breed standard as it was in 1954, from the  American Kennel Club The Complete Dog Book.

Chihuahua

SMOOTH COAT

    Head - A well-rounded apple dome skull, with or without molera. Cheeks and jaws lean. Nose moderately short, slightly pointed (self-colored, in blond types, or black). In moles, blues, and chocolate, they are self-colored. In blonde types, pink nose permissible.

    Ears - Large, held erect when alert, but flaring at the sides at about an angle of 45 degrees when in repose. This gives breadth between the ears.

    Eyes - Full, but not protruding, balanced, set well apart - dark, ruby, or luminous. (Light eyes in blonde types permissible.)

    Teeth - Level.

    Neck and Shoulders - Slightly arched, gracefully sloping into lean shoulders, may be smooth in the very short types, or with ruff about neck preferred. Shoulders lean, sloping into a slightly broadening support above straight forelegs that are set well under, giving free play at the elbows. Shoulders should be well up, giving balance and soundness, sloping into a level back. (Never down or low.) This gives a chestiness, and strength of forequarters, yet not of the "Bulldog" chest, plenty of brisket.

    Back and Body - Level back, slightly longer than height. Shorter backs desired in males. Ribs rounded (but not much - "barrel-shaped".)

    Tail - Moderately long, carried cycle either up or out, or in a loop over the back, with tip just touching the back. (Never tucked under.) Hair on tail in harmony with the coat of the body, preferred furry. A natural bob-tail or tailess permissible, if so born, and not against a good dog.

    Feet - Small, with toes well split up, but not spread, pads cushioned, with fine pasterns. (Neither the hare nor the catfoot.) A dainty, small foot with nails moderately long.

Coat - In the smooth, the coat should be soft texture, close and glossy. (Heavier coats with undercoats permissible.) Coat placed well over body with ruff on neck, and more scanty on head and ears.

    Color - Any color - solid, marked, or splashed.

    Weight - One to six pounds, with 2 to 4 pounds preferable, if 2 dogs are equally good in type, the more diminutive is preferred.

    General Appearance - A graceful, alert, swift-moving little dog with saucy expression. compatct, and with terrierlike qualities.

SCALE OF POINTS

Head, including ears............................................................................20
Body..............................................................................................20
Coat..............................................................................................20
Tail................................................................................................5
Color..............................................................................................5
Legs..............................................................................................10
Weight............................................................................................5
General appearance and action...............................................................15
                                                                                                                       ___
Total.............................................................................................100

DISQUALIFICATIONS

    Cropped tail, broken down or cropped ears.

LONG COAT

    The long-coated variety of the Chihuahua is judged by the same standard as the smooth-coated variety, except for the following:

    Coat - In the Long Coats, the coat should be of a soft texture, either flat or slightly curly, with undercoat preferred. Ears fringed (heavily fringed ears may be tipped slightly, never down), feathering on feet and legs, and pants on hind legs. Large ruff on neck desired and preferred. Tail full and long (as in plume).

     Disqualifications - Too thin coat, that resembles bareness.

SCALE OF POINTS

Head, including ears............................................................................20
Body..............................................................................................20
Coat..............................................................................................20
Tail................................................................................................5
Color..............................................................................................5
Legs..............................................................................................10
Weight............................................................................................5
General appearance and action...............................................................15
                                                                                                                       ___
Total.............................................................................................100

 DISQUALIFICATIONS

   Cropped tail, broken down or cropped ears, too thin coat, that resembles bareness.

Approved January 12, 1954.