Date: Sat, 26 Sep 1998 20:18:41 -0600 (MDT) From: chrst@srv.net To: cp@opus.hpl.hp.com Message-Id: <aabcdefg3124$foo@default> Subject: for people without access to the WWW World's Smallest
http://daphne.palomar.edu/wayne/1wayindx.htm
Wayne P. Armstrong's Key To The Lemnaceae Of North America.
http://daphne.palomar.edu/wayne/plmar96.htm
World's Smallest Flowering Plant!
There are approximately 250,000 species of described flowering plants in the
world, and they range in size from diminutive alpine daisies only a few
inches tall to massive eucalyptus trees in Australia over 300 feet tall.
But the undisputed world's smallest flowering plants belong to the genus
Wolffia, minute rootless plants of the duckweed family (Lemnaceae) that float
at the surface of quiet streams and ponds. Each plant is shaped like a
microscopic green football with a flat or rounded top depending on the
species. They reproduce exponentially by budding, and during warm summer
months they literally cover the water surface like masses of granular, green
Malto-Meal. Two of the smallest species are W. angusta, an Australian species
recently described in 1980 by Dr. Landolt, and the worldwide tropical species
W. globosa. The entire plant body of these two species is less than one mm
long (less than 1/25th of an inch) and it is difficult to say which is the
smaller of the two, but perhaps W. globosa may be slightly smaller! An
average individual plant is 0.6 mm long (1/42 of an inch) and 0.3 mm wide
(1/85th of an inch). It weighs about 150 micrograms (1/190,000 of an ounce),
or the approximate weight of two ordinary grains of table salt! One plant is
165,000 times shorter than the tallest Australian eucalyptus tree and 7
trillion times lighter than the most massive giant sequoia tree. It is small
enough to slip through the eye of an ordinary sewing needle, and at least
5,000 plants could be packed into a thimble. Each plant produces a
microscopic flower inside a small cavity that develops on the upper side of
the plant body. The minute flower consists of a single pistil and stamen.
Since the stigma is generally receptive before the anther is mature, a
condition known as protogyny, the flower typically requires cross
pollination from a different wolffia plant with a mature anther that is
ready to shed its pollen. A bouquet of one dozen plants in full bloom will
easily fit on the head of a pin! After pollination the ovary develops into a
tiny one-seeded fruit called a utricle, which also holds the record for the
world's smallest fruit.
-------------------------------------------
Hmmmm, I was thinking about the people who use the CP Mailing List, but don't
have access to the World Wide Web.
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:31:36 PST