part of part of small intestine smooth muscle muscle layer of small intestine circular muscle layer of muscular coat small intestine smooth muscle circular layer circular layer of small intestine muscularis propria circular muscle of small intestine A circular muscle layer of muscular coat that is part of a small intestine smooth muscle. MA:0001560 EMAPA:37562 circular muscle coat of small intestine circular muscle layer of small intestine short pitch helicoidal muscle layer of small intestine stratum circulare tunicae muscularis intestini tenuis UBERON:0012401 FMA:14935 stratum circulare (tunica muscularis)(intestinum tenue) SCTID:54658003 stratum helicoidale brevis gradus tunicae muscularis intestini tenuis