Anatomie. — ''Are the cross-striated muscle fibres of the extremities 

 also innervated si/mpatheiicallj/r' By Dr. Erik Agduhr. (Com- 

 municated by Prof. J. Bo eke). 



(Communicated in the meeting of 25 Jan. 1918). 



In the Anatomischer Anzeiger, Bd. 44 Boeke ') gives an account of 

 how he has shown morphologically that the cross-striated muscle 

 fibres in (he m. obliquus ocnli superior of the cat are innervated not 

 only by cerebral but also by sympathetic nerves. He describes 

 how he made a section of the n. trochlearis near the basis of the brain 

 and let the animal live till the nerve fibres that had been cut off, 

 peripherically of the place where the sections were made, had under- 

 gone degeneration that could be proved morphologically. He also 

 found in BiELSCHOWSKY-impregnated sections from the m. obliquus 

 oculi of the animal that the medullated nerves had undergone dege- 

 neration. By the side of these degenerated cerebral nerves Boeke 

 found, however, intact nerves free from medullary sheaths, which 

 ended in terminal loops in or on the muscle fibres. 



BoEKE was able to show that the terminal loops had a hypo-lemmal 

 position and on account of this he is of the opinion, that the intact 

 nerves are of an efferent nature. The position on the muscle fibres 

 of the terminal loops of these nerves was partly inside and partly 

 outside the region of a motor plate. In this way Boeke had of course 

 put forward evidence of the innervation of the cross-striated muscle 

 fibres by sympathetic nerves as well. 



This morphological evidence of Boeke has caused me to investi- 

 gate the occurrence of such nerves in the musculature of the extre- 

 mities. It is well known, that the inner orbital muscles are exceed- 

 ingly well supplied with nerves, and the possibility that only these 

 and no other cross-striated muscles are innervated sympathetically 

 is of course quite a reasonable one, even though it is not obvious. 

 During my investigations on the plurisegmental innervation of the 

 separate cross-striated muscle fibres I had in addition observed in 

 the muscles of the extremity a number of terminal organs of nerves, 

 which I could not interpret with certainty. I had also noticed a 



') Boeke, J. Die doppelte (motorische und sympathische) efïerente Innervation der 

 quergestreiften Muskelfasern. Anat. Anz., Bd. 44, 1913. 



