270 NEW YORK STATE MUSEUM 



12, a), so aggregated as to have, on a superficial examination, the 

 appearance of an oblong mass. 



The infra-esophageal ganglia have, before the removal of the 

 sheath, the appearance of a flattened, circular mass, with a 

 central opening through which passes a large artery. When the 

 sheath is removed, it is seen that the ganglia form two masses 

 aggregated together, making a sub-circular mass. The upper 

 mass is composed of five subovate ganglia, of nearly equal size 

 (pi. 12, &). One is situated dorsally and centrally, and two on 

 each side of this one. The lower part consists of two larger ovate 

 ganglia, joined to each other and to the ganglia above them. 



The buccal ganglia are small, somewhat kidney-shaped bodies 

 (pi. 12, n). 



The ganglia of the superior tentacles are subpalmate in form, 

 the palm being unduly developed, and the fingers very short (pi. 

 12, el 



The ganglia of the inferior tentacles are pear-shaped (pi. 12, i). 



The commissures connecting the supra and infra-esophageal 

 ganglia are of equal size. The upper commissures proceed from 

 the posterior part of the outer supra-esophageal ganglia, and are 

 connected with the anterior part of the lower ganglia of the upper 

 part of the infra-esophageal ganglionic mass (pi. 12, c). The lower 

 commissures proceed from the outer ones of the small, nearly 

 round ganglia of the supra-esophageal ganglionic mass, and are 

 connected with the lowest two ganglia of the infra-esophageal 

 ganglionic mass, or, as they are sometimes designated, the pedal 

 ganglia (pi. 12, c). 



From the inner anterior part of the principal supra-esophageal, 

 or cerebral ganglia, proceeds a large, conspicuous nerve, which 

 connects with the ganglia at the extremity of the superior or ocu- 

 lar tentacles (pi. 12, d, e). This nerve, after entering the tentacle, 

 gives off a nerve which proceeds to the eye, the optic nerve 

 (pi. 12, /, g); also from the outer anterior part of each ganglia a 

 nerve proceeds to the mouth and adjacent integument. 



From the central anterior part proceed two very delicate nerves 

 which continue to the integument of the superior tentacles. 



