just behind, or perhaps just offshore; the presence of 
large, heavy grains also supports this. The relatively 
high percentage of mangrove pollen suggests that a 
mixed Rhizophora swamp was present in the vicinity. 
The higher percentage of R. Mangle-type pollen and 
the marine shells may indicate more coastal conditions 
than those suggested by samples I and II. 
The two samples from Portugal (V and V1) are simi- 
lar in lithology and in the presence of moderate per- 
centages of Rhizophora pollen which is referable to the 
Rhizophora spp. division. The majority of the pollen is 
made up of various unidentified tricolpate and monocol- 
pate pollen. Small quantities (8-7%) of Engelhardtia- 
type grain occur. Sample VI contains several interesting 
non-rhizophoroid grains, among them large planar tet- 
rads comparable to those of the Annonaceae and a grain 
of Pachira aquatica Aubl.,a member of the Bombacaceae 
today characteristic of fresh-water swamp regions behind 
the mangrove as well as of streamsides. On the basis of 
these non-rhizophoroid grains, these samples would ap- 
pear to represent a somewhat less brackish facies than any 
of the above and suggest deposition in a swamp forest 
adjacent to mangroves. However, the presence of marine 
fossils in the same samples casts some doubt on this 
interpretation. 
Pollen in Sample VII, a coarse-grained siltstone from 
the Las Cruces slide, was infrequent and poorly pre- 
served. Those grains encountered appeared to be Rhizo- 
phora, perhaps of the R/zzophora spp.-type. A relatively 
large piece of amber, however, from Las Cruces has 
oysters embedded in the surface, indicating that the resin 
was still soft when it entered the marine environment. 
This suggests either that the trees producing the resin 
were growing along the shore or that the resin was trans- 
ported only a short distance before the shells were 
caught. in it. 
[ 317 | 
