Classification and ordination overlay

Dear list,

I am facing a problem when I overlay classification in ordination. I use
ordihull function (vegan package) and it gives me a rough idea of clusters
in the plant community that I am looking at.

Is there any functions in vegan package or in different packages that does
what TWINSPAN does when you look at the dendrogram of the cluster analysis
of the samples
(http://www.pisces-conservation.com/caphelp/index.html?non_metricmultidimens
ionalsc.html)?

Many thanks

Federico Tomasetto
PhD Student
?