Original URL: http://www.colby.edu/info.tech/BI211/info.html

Flowering Plant Family Identification


This WWW form is an implementation of the Hansen and Rahn punched card system for flowering plant family identification, published by Regnum Vegetabile. It is comprehensive to enable world wide flowering plant identification. In the original form, each card of the deck was labelled as one character, there being 172 cards in the deck. On each card there were 411 numbered circles, each corresponding to family of flowering plants. If the characteristic listed on the card was known to be present in at least one member of a family, that family number was punched open.

The process of identification required sorting through the deck of cards, pulling out those that were present in the speciment that was being identified, putting this set of cards together in a stack, holding the stack of cards up to a light source, and seeing which family numbers were punched through on all the cards in the stack. If a suitably large number of characters are selected, only a single family number will be punched on all the cards, and the identification will have been made. More typically, a number of families will be identified as possible.

The punch card system is a process of elimination. Selecting a card excludes certain families because their numbers are not punched on that card. Because a family number is punched if ANY member of the family has that feature, only those families that the specimen could not possibly be are determined by each selection. If a mistake is made in selecting a card because of misinterpretation of the character or in examining the specimen, misidentification might occur.

Electronic forms of this identification system were developed by Ray Phillips at the University of Oklahoma and at Colby College. Versions were developed for UNIX systems and enhanced capabilities in a Macintosh application. This version uses the same data in a WWW form with the same search algorithms as the earlier ones and functionally equivalent to the original card system.

This system is amenable for the identification of other taxa.

Comments and suggestions should be directed to Ray Phillips, Director of Information Technology Services and Assistant Prof. of Biology, Colby College, Waterville, ME 04901.

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