I am responding to Donald’s
questions as they apply at
As several have described, there are
multiple layers of identification that occur with specimens, particularly botanical
specimens.
Our physical herbarium specimens are
structured in a hierarchy, starting from the original plant that was collected
down to individual pieces with labels.
COLLECTION
Identification begins at collection.
Multiple “samples” are usually taken from one plant or an entire
small plant may be taken, a collector’s number is assigned to the
sample in the collector’s field book along with notes and samples also
numbered. Samples of other plants of the same kind may also be taken with
different numbers assigned to each in the field book and on the sample.
Samples may be made up of multiple pieces - leaves and stems, fruits,
seeds, bark, etc. – some may be dried, others left wet. All of the
pieces/samples of the one plant described in one numbered field book entry
belong to the one organism noted by the collector.
PREPARATION
The pieces of dried or wet samples are
shipped back to MBG with their identifying numbers. Nowadays, the
information from the field book is recorded in Tropicos including the
collector’s number. A unique TropicosID number is assigned in
database to the specimen or “sample” and the data from the field
book is recorded including the collector’s name and number. Accession
numbers are assigned to each of the pieces of the sample that will be “mounted”
in a different way. A mounting sheet has the accession number pre-printed
on the sheet and the number applies to whatever is mounted on the sheet. But,
a separate large fruit from the same plant would be put in a bag for instance and
assigned a different accession number. Nowadays, these accession numbers
are also recorded in Tropicos. A label is printed for the sheet and duplicate
labels are printed for each of the related “accessions”. They
are all the same label with the TropicosID and collector’s number on them.
DUPLICATES
Labels are also printed for the “duplicate”
samples but no accession numbers are assigned to them and they are not
mounted. The duplicates may be sent unmounted to specialists for
determination or to other herbaria. The identification of these samples/specimens
is what is printed on the included label – which includes Tropicos ID,
Collector’s Name and Collector’s Number. The receiving
institution may or may not assign additional numbers, mount the sample on a
sheet, database it, etc. Totally up to them.
MOUNTING
The flat pieces are mounted on the sheets,
large samples may require multiple sheets for one copy. Large things (fruits,
bark, branches) may be put into bags or other holding methods. A barcode
number is attached to the sheet and any additional pieces/accessions and
recorded in Tropicos. A different barcode is on each piece or accession. So,
barcodes have a one-to-one match to accession numbers. The duplicate printed
labels are also attached to the sheet and any related pieces/accessions. If
an attached barcode comes off and is lost, a new, replacement barcode is
attached and updated in Tropicos.
The use of Lead Collector’s Last
Name and field book (also called catalog) number is very common in botany –
eg. CROAT 10100. The collector-number method is frequently used in reference
literature plus the addition of the Index Herbariorium code for the institution
where the specimen was seen or gotten from. Duplicates of CROAT 10100
could be at MO, K, P, F, etc. and those sheets may have different accession
numbers or no accession number at all.
Donald’s Questions:
On one mounted specimen sheet
at MBG are the following numbers/identifiers:
- Accession
number (100% unique)
- Barcode number
(100% unique)
- Tropicos ID (applies to
all accessions and barcodes for one sample/specimen)
- Collector’s name
and number (applies to all accessions, barcodes, TropicosIDs, and duplicate
samples/labels sent to other institutions from the original collected organism)
All of these numbers are
recorded in the Tropicos database.
I attempted to describe
this above.
Collector’s numbers
are commonly unique to a collector and don’t repeat across notebooks, but
the numbers are not unique themselves and are only unique when combined with
Collector’s name
Accession numbers and
barcodes are unique to the sheet/bag they are attached to and are one-to-one
with each other and are unique within the institution
TropicosID is unique within
the database and the institution and is supposed to be one-to-one with collector/collector
number.
Lead collector last name plus
number is unique within the database and within the institution but not unique
globally.
Described at the
beginning.
The primary search for
specimens in Tropicos is by collector name and number.
Technically, it would
require addition of an “alias” identifier and additional
programming to enable searching on the alias.
Since there are 4
identifiers in hierarchical relationship, which of them could be the “single”
identifier? This goes to my continuing question of “what are we
trying to identify”? The original specimen (and its duplicates), a
specific sheet, a specific part of a sheet, or part of a specimen in an alcohol
bottle separate from the sheet?
By subsample, are we
referring to the occurrence of “duplicates” of the original
organism or rather to the pieces of it, like bark, fruit, leaves? What
constitutes the “specimen” versus the sample? We really need
to sharpen the language in these discussions to eliminate the round-robin
responses that occur as everyone states their opinion of what they think the
terms mean but no one decides exactly the definition to be used by everyone.
The biggest issue to me is
that there are no standards for identification of anything below the level of
the original collecting event and even the collector name + number is just a
common practice in botany, not a “standard” and not universal by
any means. The term “accession” means different things to
different institutions. Accession number at MBG refers to an associated part
of a specimen, not the whole specimen. Does catalog number mean the same thing
everywhere? To some it means the collector’s number.
I suppose another issue
is that because of the common practice in botany of collecting duplicate
samples and sending them around to other institutions, any worldwide count of databased
specimens that does not account for these duplicates will overstate the real number.
The subject of specimen identifiers is somewhat linked to
that of collection identifiers, since Darwin Core and the ABCD Schema have used
institution and collection codes together with catalogue numbers to identify
specimens in the absence of GUIDs. It would also be useful here to
collect information on the following:
We don’t separate
our collections into sets, they are all part of one herbarium collection.
Accessions combine into one
specimen.
Duplicate specimens can be
at other institutions.
We do record the
institutions where we know duplicates of a specimen are located but we do not record
the other institution’s catalog numbers
Previously discussed.