( He ( ( inserts ( ( a structure ) ( ( called ( a spicule ) ) ( into ( ( the ( hermaphrodite 's ) ) vulva ) ) ) ) ) . ) )
(ROOT (S (NP (PRP He)) (VP (VBD inserts) (SBAR (S (NP (DT a) (NN structure)) (VP (VBD called) (NP (DT a) (NN spicule)) (PP (IN into) (NP (NP (DT the) (NN hermaphrodite) (POS 's)) (NN vulva))))))) (. .)))
He inserts a structure called a spicule into the hermaphrodite's vulva.
(ROOT (S (NP (NP (DT The) (JJ sharp) (NNS projections)) (SBAR (IN that) (S (NP (JJ specialized) (NNS cells)) (VP (VBP grow))))) (VP (VBP are) (VP (VBN called) (NP (NNS spicules)))) (. .)))