A Close-up View of the



Celosia argenta

by Brian Johnston   (Canada)

The unusually shaped bloom of this plant is best described as “bizarre” or “weird”!  A bright red, flattened fan shape is topped by a series of convoluted ridges to form a flower-head composed of hundreds of tiny individual flowers.  The bloom is approximately 13 centimetres high, and 12 centimetres wide at the top.  The flattened triangular base is about 2 centimetres thick.

Celosias are members of the amaranth family (Amaranthaceae).  The particular cut-flower photographed for this article is a cultivar of wild Celosia argenta called “cristata”.  Wild celosias are native to the equatorial tropics of Africa, Asia, and South America.  The common name for the plant comes from the flower-head’s resemblance to a rooster’s comb.  Alternative common names are “feathered amaranth”, “wool-flower”, and “red fox”.

In the closer view below, the small individual flowers growing in the triangular base are just visible.  The flowers at the bloom’s base are lighter coloured than those positioned higher up.


The plant’s fleshy stem has a large diameter, and is strongly ridged.  Notice the tiny membranous “leaflets” (for want of a better word), that grow randomly from the orange-pink ridges.



As can be seen below, the tiny flowers are very tightly packed on the flat surface of the flower-head.  They bloom in order from bottom to top.  The many cream coloured specks are actually the flowers’ anthers.


Just below the fringe at the top of the bloom there are many unopened, tightly packed, torpedo-shaped buds.


A closer view of the convoluted fringe shows it to be composed of many overlapping bract-like structures with cream coloured bases, and bright crimson pointed tips.


A bright yellow band separates the two sides of the bloom’s fringe.


When viewed from above, the folded shape of the fringe becomes evident.  The many bright red “hairs” growing out from the yellow tissue are less than a millimetre in length!


The close spacing of the plant’s flowers can be seen below.


Flowers are spaced farther apart on the narrow “edge” of the triangular section of the flower-head.


The flowers shown below are completely open.  If you look very carefully at the image on the right, you may be able to distinguish stamens, and the occasional pistil in the flowers’ open ends.


Several additional views of flowers at higher magnification can be seen below.


In the very high magnification view of a single flower that follows, notice that the bases of the pink petals are green in colour.  Also note the tiny “bractlets” at the top of the flower’s short stalk.


Close study of the flowers below reveals the oval, cream coloured anthers (male pollen producing structures) and bright pink, hair-like pistils (female pollen accepting structures) that constitute the reproductive organs.


Under the microscope, the arrow-shaped anther can be seen to be liberally coated with pollen grains.  Notice the bright red filament that supports the anther.


Two examples of pistils from different flowers are shown below.  The stigma has about the same diameter as the style that supports it.  Pollen grains clinging to the stigma can be seen clearly in the image on the right.


A much higher magnification of the stigma reveals the tiny spherical protuberances on its upper surface.


At the base of the pistil, there are a number of roughly spherical “fruit”.  The higher magnification image on the right shows surface detail, and an “out of place” pollen grain.


The bright green lance-shaped (lanceolate) leaves of the plant are strongly veined.


Views of a leaf’s upper surface (left), and cellular structure (right) follow.  Note the many pollen grains clinging to the leaf’s surface.


The back surface of a leaf is more contoured than the front.


The extraordinarily shaped and coloured flowers of the cockscomb make it ideal for use in large-scale planting in public places.  The unusual blooms certainly provoke comment!

Photographic Equipment

Most of the macro-photographs were taken with an eight megapixel Canon 20D DSLR equipped with a Canon EF 100 mm f 2.8 Macro lens which focuses to 1:1.  A Canon 250D achromatic close-up lens was used to obtain higher magnifications in several images.

A few photographs were taken with an eight megapixel Sony CyberShot DSC-F 828 equipped with achromatic close-up lenses (Canon 250D, Nikon 5T, 6T, Sony VCL-M3358, and shorter focal length achromat) used singly or in combination. The lenses screw into the 58 mm filter threads of the camera lens.

The photomicrographs were taken with a Leitz SM-Pol microscope (using a dark ground condenser), and the Coolpix 4500.

A Flower Garden of Macroscopic Delights

A complete graphical index of all of my flower articles can be found here.

The Colourful World of Chemical Crystals

A complete graphical index of all of my crystal articles can be found here.

 All comments to the author Brian Johnston are welcomed.

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Published in the February 2009 edition of Micscape.
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