ICBN and typo in type citation

[Jenny Hart]

        I have a problem with a plant species name and the taxon to which it
applies due to an apparent typographical error when the type was designated.
The species (Sp. A) was published in 1849, however the type cited (giving
only the country, collector and number) is identical to that given for
another species in another genus of the same family (Sp. B) in the same
paper by the same author, four pages earlier.  The specimen cited for both
species accords with the description given for Sp. B.  Another specimen with
the same location and collector but with the last digit of the collector's
number different was found in this author's type collection.  This specimen
does agree with the description for Sp. A and would appear to be the type
intended by the author for Sp. A.
        I cannot find a part of the ICBN which may apply to this situation so:
        1. is Sp. A validly published? and
        2. is Sp. A a synonym of Sp. B given that they were published
sharing the same type? or,
        3. since it appears to have been an error, can Sp. A be
lectotypified to the intended type which agrees with the protologue? (in
which case Sp. A is a synonym for Sp. C - an earlier name for that taxon).
        Does anybody have a solution to this problem?
        Thanks
        Jenny Hart

Dr Jenny Hart                           John Ray Herbarium (SYD)
Post Doctoral Fellow               School of Biological Sciences
jmh at bio.usyd.edu.au                         Macleay Building A12
Ph:  +61 2 9351 4489                    The University of Sydney
Fax: +61 2 9351 4771                          NSW 2006 AUSTRALIA