fungal spores compared with total pollen, are summarized 
in Table I. The significance of these percentages is dis- 
cussed in a following section. 
The Ecotocy or MopERN MANGROVE 
AND ASSOCIATED VEGETATION 
The term ‘‘mangrove™’ is applied both to the physi- 
ognomically similar but taxonomically diverse group of 
salt-tolerant semi-aquatic woody plants that grows along 
silted shorelines and in brackish water throughout the 
tropics and to any member of this vegetation. The New 
World mangrove association includes four major genera: 
Rhizophora, Avicennia, Laguneularia and Conocarpus. 
Of these, only Rhizophora and Avicennia have more than 
one species. An additional minor component of man- 
grove vegetation on the west coast of Central and South 
America is Pellictera rhizophorae Pl. & Tr. Some work- 
ers would also include as *tmangroves’” plants with a 
limited salt tolerance that occur in swamps behind the 
‘true mangroves, e.g., Cassipourea (Cuatrecasas, 1958). 
The ecology of New World mangroves has been studied 
by Chapman (1989), Cuatrecasas (1958) and others. 
Lindeman (1953) has given a complete description of 
the vegetation types of coastal Surinam, including the 
mangrove, Which is extended by Muller (1959) and van 
der Hammen (1963) to the north coasts of Venezuela 
and British Guiana. Cuatrecasas (1958) has described 
the situation along the coasts of Colombia and Ecuador. 
Only brief descriptions of mangrove vegetation are 
available for Mexico and Central America. 
Studies of recent pollen sedimentation by Muller 
(1959, 1964), van der Hammen (1963) and Spackman, 
et al, (1964) indicate that, among the mangroves, only 
species of Rhizophora and Avicennia are likely to be rep- 
resented in the pollen record to any great extent. Thus, 
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