In message , Nick Maclaren
writes

In article ,
K writes:
|
| Speaking as an amateur, start by learning about families and genera.
| It's made easier by families being given names ending with 'aceae' - so
| Rosa is the genus, Rosaceae the family (which includes other genera such
| as Malus (apples), Pyrus (pears), Sorbus - rowans and whitebeams)
|
| Carrots, parsnips, fennel, dill, parsley are all in the umbellifer
| family, which appears now to be called Apiaceae. Many of our other herbs
| - mint, marjoram, oregano, savory - are Lamiaceae, named after the genus
| Lamium which includes the silver leaved dead nettle used as a ground
| cover in gardens.

Unfortunately, quite a lot of the family names have been created by the
rabid renamers - Apiaceae and Lamiaceae are two - and many/most books
use the old names (try Umbelliferae and Labiatae). There didn't seem
to be any reason for that except dogma, and the old names were often
usefully descriptive (as in those cases). What is more, the old rules
still seem to be valid, unlike for genera and species, so you have to
learn two schemes :-(

Only some of the old names are valid. Botanists standardised the names
of higher taxa as being based on a genus (not necessarily a currently
excepted genus - hence Caryophyllaceae and Theaceae), with standardised
terminations, such as -aceae for families (beforehand you'd have forms
such as Berberideae, rather than Berberidaceae), and grandfathered in a
few widely used descriptive family names - Gramineae, Legumiosae,
Compositae, Cruciferae, Guttiferae, Umbelliferae, Labiatae, Compositae,
Palmae and Papilionaceae/Papilionoideae. Other such names, such as
Columniferae (Malvaceae) or Culmineae (Tiliaceae?) aren't valid.

I seem to recall that there is a proposal to remove the remaining
descriptive family names, as they are now rarely used in botanical
works, except for Palmae. (They're is a proposal to allow Palmaceae, as
Arecaceae is a bit similar to Araceae.)

If I recall, some family names have changed half a dozen times, as the
rigid application of the rules dictated, but I don't think that many
of those have impacted most gardeners. Except for the Leguminosae
(a.k.a. Fabaceae a.k.a. Papilionaceae a.k.a. Caesalpiniaceae?), which
I have seen cause considerable confusion.


I would have thought that changes of family names followed more from
changes to classification than to following the rules of the ICBN. For
example the names you give for Leguminosae are all alternatives, but
follow from disagreement as to whether to consider the clade one family
or three.

For an example as to how classification has changed over history, I've
put together part of the story for Malvaceae

http://www.malvaceae.info/Classification/history.html

Theobroma (cacao), for example, has been in Tiliaceae, Malvaceae,
Byttneriaceae (aka Buettneriaceae), Theobromaceae (aka Theobromataceae)
and Sterculiaceae.

Regards,
Nick Maclaren.

--
Stewart Robert Hinsley