132 PRACTICAL HISTOLOGY [XVI 



the rabbit (Golgi), and in the tendons of the gastrocnemius, 

 tibialis posticus and extensor longus digitorum of the cat 

 (Huber and de Witt). They usually occur at the junction of 

 muscle and tendon. The number of tendon bundles forming an 

 organ, the distinctness of the sheath, and the spindle forms 

 vary greatly in different cases. In the tendons of the eye 

 muscle, they are not easily distinguished from the rest of the 

 tendon unless the nerve fibres are stained. In the frog the 

 difference between an ordinary tendon bundle and a tendon 

 bundle of a neuro-tendinous organ is still less. In all cases a 

 large medullated nerve fibre runs to the organ, generally from 

 the muscle, and branches ; the branches become non-medullated, 

 and form a spray of fibrils on and partly in the tendon bundle. 



