Pollen (continued)
Pollens are propagules from vascular plants and spores are the propagules from the nonvascular plants. Spores have a shell (exine)
consisting of one layer generally though a loose outer sack, the perine, may be present (see fern spores for an example). Pollens have an exine typically of two or more layers. Spores are not optically active, that is
when they are viewed between crossed polarizing filters they disappear. Pollens are often optically active or contain
starch grains that are optically active. These pollens are visible when viewed between crossed polarizing filters. As
pollen grains age they loose the optical activity and the starch grains dissipate into the environment. These starch grains
carry the allergen for that pollen with them. Most standard guides to pollen identification are based on "acetolyzed" grains,
chemicaly processed pollen that removes the contents of the grain and most of the optical activity of the grain. It also
swells the grain. This is a necessary practice in the analysis of fossil grains but for environmental analysis the fresh
pollen grain is more characteristic. Most of the pollen grains shown here are fresh. They are from honeybee frass (fecal
pellet), regional honey samples, or from recent environmental samples. An abridged morphological key is provided here (see
References at end). - Click here
to link to a good website containing a glossary of morphlogical terms used to describe pollens and spores.
Vesiculate Pollens: Pollens with air sacks to increase bouyancy. The sacks are typically two
per grain at the bottom of the grain, but may also be doughnut shaped under the grain.
(Click here for
more images in this category.)
Trilete or Trichotomocolpate: Pollens with three furrows joined at one pole.
Inaperturate Pollens: Pollens without air sacks that don't have any visible openings in the exine.
Polyplicate: Pollens with numberous sharp meridional ridges.
Monocolpate: Pollens with one furrow and without an associated pore or transverse furrow.
Dicolpate: Pollens with two furrows and without associated pores or transverse furrows.
Tricolpate: Pollens with three furrows and without associated pores or transverse furrows.
Polycolpate: Pollens with more than three furrows and without associated pores or transverse furrows.
Stephanocolpate: Pollens as above and all the furrows are oriented meridionally
Pericolpate: Pollens as above but all the furrows are not oriented meridionally
Monoporate: Pollens with one pore and without an associated furrow.
Diporate: Pollens with two pores and without associated furrows.
Triporate: Pollens with three pores and without associated furrows.
Stephanoporate: Pollens with more than three pores and all pores are located equatorially.
Periporate: Pollens as above but the pores are not located equatorially.
Heterocolpate: Pollen with furrows and pores but not every furrow has a pore.
Tricolporate: Pollen three furrows, each with a pore.
Polycolporate: Pollen with more than three furrow, each with a pore.
Stephanocolporate: Pollens as above and all the furrows are oriented meridionally
Pericolporate: Pollens as above but all the furrows are not oriented meridionally
Fenestrate: Pollen with geometrically positioned large openings in the "tectum", some with pores.
Polyad: Pollen consisting of more than one grain.
(Click here for
more images in this category.)
Faegri, Knut and Johs Iversen, TEXTBOOK OF POLLEN ANALYSIS, Hafner Publishing Company, 1964.
Kapp, Ronald O., HOW TO KNOW POLLEN AND SPORES, Wm. C. Brown Company, 1969.
Moore, P.D., J. A. Webb, and M. E. Collinson, POLLEN ANALYSIS, Blackwell Scientific Publications, 1991
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