288 NEW YORK STATE MUSEUM 



ocular tentacular muscles (3), and the retractor muscles of the 

 buccal body (5). The superior, or ocular tentacular muscles, 

 shortly subdivide, giving origin to the muscles of the inferior, or 

 olfactory tentacles (4), which are much smaller than those of the 

 ocular tentacles. 



The muscular sheath of the supra-esophageal ganglia is con- 

 nected with the superior tentacular muscles by two flat muscular 

 bands on each side (pi. 20, fig. 1, 2). 



In the anterobasal part of the animal arises a set of three 

 muscles on each side (pi. 19, 20, fig. 1), the posterior one (1) arising 

 under the muscles of the superior tentacle, and inserted near the 

 lips of the animal. The middle one (8) is inserted in the muscles 

 of the inferior tentacle. The anterior and largest muscle (5) 

 passes over the superior tentacle muscles and is inserted at the 

 mouth. 



Posterior to these a muscle on each side has its origin in the 

 basal part of the animal, and is inserted in the muscle of the in- 

 ferior tentacle (10). 



In figure 2, plate 20, the retractor muscles have been cut close 

 to the buccal body, and that organism has been turned forward 

 to show its under side, and also the base of the anterior part of 

 the body cavity. 



On each side of a basal median line, and at a short distance 

 from it, a thin, flat band of muscular fibres arises, which is in- 

 serted at the extreme anterior end of the body at the mouth, im- 

 mediately below the anterior end of the buccal body {1). These 

 two bands of muscles, at their anterior part cross each other at 

 an angle of about 45°. Their function is to contract the basal 

 part of the anterior portion of the body. 



On each side of the buccal body the lower part of the lateral 

 lips can be observed, showing as a white mass, somewhat regu- 

 larly longitudinally divided. From the posterior part of each 

 mass proceed two muscles, one broad, the other narrow, uniting 

 with the muscles of the inferior tentacle (pi. 19. fig. 2, 3). 



On the right side of the figure the lip and its muscles are shown 

 in their natural position; on the left side of the figure the lip and 



