Gulf Fritillary host plants.

[Carol R. Lemmon]

Mark,
 
Try looking for  Passifloras that are native to the U.S., such as P.
caerulea, P. incarnata, or P. suberosa.  Passiflora suberosa is a very
common roadside vine in the Gulf Fritillary's range, but the flowers are
rather small and unspectacular.  I have personally raised many Gulf
Fritillary larvae, as well as Zebra Longwings on this species.  The other
two species are more locally common, and have large (3-4") purple and white
flowers.  If you are unwilling to obtain a wild plant, either through
digging up (only do so if there are many plants in the area), cuttings
(rather easy to do with rooting powder), or seeds (the slowest way), I'm
sure some of your local garden centers must have one or more of these
species.

Regarding the plants you already had, they were probably not poisonous to
the larvae, just distasteful.  So they might of starved to death. 
Passiflora vitifolia is not known to be a good hostplant for Gulf
Fritillaries, neither is the similar P. coccinea, which is also bright red.

Good luck.

Jeff Fengler
Reasearch Assistant
Connecticut Agricultural Experiment Station