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WELCOME TO DESMIDS DOT COM
There is some very sad news to add to this site. William Ells passed away today (7th December 2009) and he will be sorely missed by his wife, family and friends. He reached the fine age of 92 years, but his passing leaves a hole in all of our hearts. Please visit the IN LOVING MEMORY page where you can leave a comment for others to see. I will continue to keep this site running as it has visitors from around the world who are interested in my grandfathers drawings, photographs and observations of desmids. Rest in peace granddad [Richard Ells]
Desmids Dot Com is the web page of Bill Ells an amateur microscopist. Bill has been studying microscopic freshwater pond life since 1976, mainly the algae, and from about 1980 specialising on the desmids. Unusual fauna are noted and the details passed on to other specialist.
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"WHAT ARE DESMIDS ?"
This article first appeared in the spring/summer issue 1992 of Kent Wildlife Focus
The magazine for members of the Kent Trust for Nature Conservation (now Kent Naturalist Trust)
The Director of a local Nature Conservation Trust asked "what are desmids" when I told him I had found some in a small acid bog at Hothfield in Kent. Twenty years ago I was asking the same question. The majority of Naturalists study birds, as is evident by the great number of books on birds published every year. Butterflies and flowering plants are also popular subjects. If you study flies; millipedes; spiders; or anything most people find repulsive you will be thought eccentric, if you study algae your mental condition will be considered unstable.
ALGAE
Desmids are an attractive and unusual group of freshwater algae. They are microscopic flowerless plants without roots; stems; or true leaves. In fact complex single cells, some are the largest single cells in the Plant Kingdom, the largest can just be seen with the unaided eye.
Many of the more complex types are divided into two semi-cells by a distinct isthmus or constriction, once thought to be a pair of joined cells, hence the name desmid derived from 'desmos' Greek for a bond or chain. Desmids belong to a group of algae; the group includes some non desmid filamentous types; that come together, usually when their habitat is drying out, in a process known as conjugation to form resting spores, from which new plants will grow when the right conditions prevail . The more common method of reproduction is by the impossible mathematics of multiplying by dividing, usually at the constriction .
They possess three perfect planes of symmetry and exhibit an incredible diversity of shapes .
In addition to their remarkable variation in shape the cellulose walls of many species are ornamented with granules, spines or wart like protuberances arranged in complex, yet orderly and symmetrical patterns. They are coated in a clear jelly like substance known as mucilage which can be shown by adding Indian ink to the water . Some are joined together to form quite long filaments which the beginner could confuse with the more common filamentous algae that forms 'blanket weed' on ponds.
Do they have common names? No, because they are not commonly seen ! but don't let the scientific names deter you from studying them. I only know the meaning of a few of them and cannot pronounce many of them.
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