<Tr> <Th> FMA </Th> <Td> 49151 </Td> </Tr> <Tr> <Td_colspan="2"> Anatomical terms of muscle (edit on Wikidata) </Td> </Tr> <P> The ciliary muscle / ˈsɪli. ɛər i / is a ring of smooth muscle in the eye's middle layer (vascular layer) that controls accommodation for viewing objects at varying distances and regulates the flow of aqueous humour into Schlemm's canal . It changes the shape of the lens within the eye, not the size of the pupil which is carried out by the sphincter pupillae muscle and dilator pupillae . </P> <P> The ciliary muscle develops from mesenchyme within the choroid and is considered a cranial neural crest derivative . </P>

What is the function of the ciliary muscle