1897.] NEW YORK ACADEMY OF SCIENCES. 85 



the Accessorj^ and centrally into the main trunk of the Acces- 

 sory, the ultimate destination of the latter being unknown. 



The usual communication of the Third Cervical with the Spinal 

 Accessory in the Cynomorpha is seen in the plexus of Macacus 

 rhesus (Fig. I., 5). 



Another form of the anastamotic connection between the upper 

 cervical nerves and the Spinal Accessory is presented by the plex- 

 us of ilfacacws p^7ea^MS, Plate YI., (Fig. II.), also throwing some 

 light on the probable derivation of the human Occipitalis minor. 



Here the Third Cervical gives otf, in addition to the Auricularis 

 magnus (Fig. II., 1), and the two divisions of the Superficial 

 Cervical (Fig. II., 3, 3'), a communicating branch of considera- 

 ble size (Fig. II., 2), which passes in great part into the Sterno- 

 mastoid branch of the Accessory (Fig. II., 5), travelling centrally' 

 within the sheath of the nerve. The remainder of this branch 

 applies itself in two filaments to the main trunk of the Acces- 

 sor3\ accompanjnng it in a peripheral direction, for a short dis- 

 tance. It then separates again from the main trunk of the 

 Accessory, and, after junction with an additional filament from 

 the Third Cervical, forms a trunk (Fig. II., 4), which supplies 

 cutaneous filaments to the integument over the interval between 

 Sterno-mastoid and Trapezius (Levator clavicula?). Consider- 

 ing the composition of this anastomosis in comparison with the 

 human plexus we find the usual communication, with centrally 

 directed fibres, between the Third Cervical nerve and the Sterno- 

 mastoid branch of the Spinal Accessory. 



The structure and distribution of branch 4 (Fig. II.), indi- 

 cates a rudimentary Occipitalis minor. This supplies a second 

 communicating twig to the Accessory — the fibres passing in a 

 peripheral direction — and the tegumentary nerves to the dorsal 

 zone of the cervical plexus, corresponding to the interval be- 

 tween the Sterno-mastoid and Trapezius. 



The superficial distribution of the cervical plexus in the Cyno- 

 morpha is exceedinglv rich in terminal branches, anastomosing 

 freely with each other and frequentl}^ forming loops. The}' are 

 placed under cover of the Plat^'sma, and reach the cutaneous 

 distribution by perforating this muscle. 



The general arrangement of these superficial branches is seen 

 in Plate VI., Fig. III., representing the superficial dissection of 

 the right side of the neck in a specimen of Macacus pileatus. 

 The branches may be grouped under the following heads : 



I. Auricularis magnus. 



The nerve forms a large trunk, curving around the dorsal 

 marsfin of the Sterno-cleido-mastoid and ascending on the outer 



