Another fern from Costa Rica, this is Sticherus bifidus. I took this particular picture along one of the driveways through the research station at Las Cruces; I was trying to get a good closeup of the little fiddlehead in the fork where the two pinnae meet. I didn't succeed, but this is still a nice view of the growth habit this fern takes. Its leaves fork dichotomously (in two), often several times, and a small "resting bud" (the fiddlehead) sits at the fork ready to begin growing again when the time comes. This is indeterminate growth, as opposed to determinate, where the leaf grows to a certain size and then stops. Often the bud will grow vertically upwards, through other vegetation, and when it overtops its immediate neighbors it will then send out new pinnae to the sides, and the bud will rest until it's time to grow again.