Identification of beta fibers at spindle entry.
D000818:Animals; D006652:Histological Techniques; D008394:Marsupialia / Q000033:anatomy & histology*; D009470:Muscle Spindles / Q000033:anatomy & histology*; D009132:Muscles / Q000033:anatomy & histology; D009210:Myofibrils / Q000032:analysis; D012911:Snakes / Q000033:anatomy & histology*; D013045:Species Specificity