( ( ( ( ( ( ( In ferns ) ( , ( ( the ( young fronds ) ) ( develop ( by ( ( ( uncurling along ) ( the ( main axis ) ) ) ( from ( ( the base ) ( towards ( the tip ) ) ) ) ) ) ) ) ) ) ; ) ( ( ( this type ) ( of ( vernation ( -LRB- ( ( leaf development ) -RRB- ) ) ) ) ) ( ( ( is ( known ( as ( circinnate vernation ) ) ) ) and ) ( is ( ( a ( distinctive characteristic ) ) ( of ferns ) ) ) ) ) ) ; ) ( ( the ( uncurling frond ) ) ( is ( known ( as ( a ( ( fiddlehead or ) crosier ) ) ) ) ) ) ) . )
(ROOT (S (S (PP (IN In) (NP (NNS ferns))) (, ,) (NP (DT the) (JJ young) (NNS fronds)) (VP (VBP develop) (PP (IN by) (S (VP (VBG uncurling) (PRT (RP along)) (NP (DT the) (JJ main) (NNS axis)) (PP (IN from) (NP (NP (DT the) (NN base)) (PP (IN towards) (NP (DT the) (NN tip)))))))))) (: ;) (S (NP (NP (DT this) (NN type)) (PP (IN of) (NP (NP (NN vernation)) (PRN (-LRB- -LRB-) (NP (NN leaf) (NN development)) (-RRB- -RRB-))))) (VP (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (JJ circinnate) (NN vernation))))) (CC and) (VP (VBZ is) (NP (NP (DT a) (JJ distinctive) (NN characteristic)) (PP (IN of) (NP (NNS ferns))))))) (: ;) (S (NP (DT the) (VBG uncurling) (NN frond)) (VP (VBZ is) (VP (VBN known) (PP (IN as) (NP (DT a) (NN fiddlehead) (CC or) (NN crosier)))))) (. .)))
In ferns, the young fronds develop by uncurling along the main axis from the base towards the tip; this type of vernation (leaf development) is known as circinnate vernation and is a distinctive characteristic of ferns; the uncurling frond is known as a fiddlehead or crosier.
(ROOT (S (NP (NP (DT The) (JJ first) (NNS leaves)) (PP (IN of) (NP (JJS most) (NNS ferns)))) (VP (VBP appear) (SBAR (S (VP (VBD curled) (PRT (RP up)) (PP (IN into) (NP (NNS fiddleheads))))))) (. .)))