( ( ( ( The majority ) ( of gastropods ) ) ( have ( simple ( visual organs ) ) ) ) ( , ( eye ( ( ( spots either ) ( at ( ( the ( ( tip or ) base ) ) ( of ( the tentacles ) ) ) ) ) . ) ) ) )
(ROOT (S (S (NP (NP (DT The) (NN majority)) (PP (IN of) (NP (NNS gastropods)))) (VP (VBP have) (NP (JJ simple) (JJ visual) (NNS organs)))) (, ,) (NP (NN eye)) (VP (VBZ spots) (ADVP (RB either)) (PP (IN at) (NP (NP (DT the) (NN tip) (CC or) (NN base)) (PP (IN of) (NP (DT the) (NNS tentacles)))))) (. .)))
The majority of gastropods have simple visual organs, eye spots either at the tip or base of the tentacles.
(ROOT (S (NP (DT A) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (NNS gastropods)) (VP (VBZ is) (VP (VBN noted) (PP (IN for) (S (VP (VBG having) (NP (PRP$ its) (NNS eyes)) (PP (IN at) (NP (NP (DT the) (NNS tips)) (PP (IN of) (NP (NNS stalks) (CC or) (NNS tentacles))) (SBAR (WHNP (WDT that)) (S (VP (VBP emerge) (PP (IN from) (NP (PRP$ its) (NN head))))))))))))) (. .)))