RIGHT |4. RIGHT RING |5. RIGHT LITTLE 22| 11| MIDDLE 19| O| O | | | | [Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration] | | | | --------------------------------------------------------------------------- \ | \ | \ | W | W --------------------------------------------------------------------------- 1. LEFT THUMB |2. LEFT INDEX |3. LEFT M|4. LEFT RING |5. LEFT LITTLE 18| 10| MIDDLE I| I| 13 | | | | [Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration] | | | | --------------------------------------------------------------------------- / | / | W | W | / --------------------------------------------------------------------------- WCDX EXTENSION: In the extension used in the Federal Bureau of Investigation for the large whorl groups, the type of whorl is designated by the symbols W, C, D, or X for the index fingers and w, c, d, or x for all other fingers, according to its classification as defined in figure 354. These symbols are used for subclassification purposes only and are brought up into the classification formula directly above the subsecondary in their respective positions, the right hand being the numerator, the left hand being the denominator. SPECIAL LOOP EXTENSION: In the all-loop group (1R-U) ------ (1R-U), the following special loop extension may be used, utilizing the ridge counts in fingers Nos. 2, 3, 4, 7, 8, 9, and, if necessary, No. 10: _Ridge Counts_ _Value_ 1 to 4, inclusive 1 5 to 8, inclusive 2 9 to 12, inclusive 3 13 to 16, inclusive 4 17 to 20, inclusive 5 21 to 24, inclusive 6 25 and over 7 The resulting values in this extension are brought up into the classification formula directly above the subsecondary in their respective positions, the right hand being the numerator, the left hand being the denominator. In addition to the extensions already mentioned, fingerprint groups may be divided into male and female, and by age (either by year or by arbitrarily setting an age limit, beyond which a print bearing such an age would be filed separately in a "Reference" or a "Presumptive Dead" file).