THE GEPHYREA OE JAPAN. 27 



served in formalin and therefore keeps the natural color almost 

 unchanged. 



The animal is of a moderate size (Fig. 7), the body proper 

 measuring about 30 mm. in length and 9 iniii. in maximum 

 breadth. The introvert, which is entirely retracted, is much 

 more slender than the body proper, being only about 2 mm. 

 thick. The body- wall is yellowish brown and is covered with 

 large, variously shaped papillae of a deep brown color. In the 

 middle region of the body proper, the papillœ are but slightly 

 elevated bodies of 0.25 mm. basal diameter, each consisting of 

 ])olygonal chitinous plates of a deep brown color and various 

 sizes (Fig. 56). The small lighter colored area (marked with 

 X in the fig.) in the centre of the papilla, is perforated by the 

 minute external opening of the subdermal gland. The non- 

 pa pillated parts of the surface, in this region of the introvert, 

 is covered with sparsely scattered chitinous plates which seem 

 to be of the same character as those of the papillœ. On the 

 introvert-basis as well as in the posterior region of the body 

 proper, the papilhe are conspicuously tall, taking the shape of 

 an obtusely apexed cone (Fig. 57«, taken from the region of the 

 introvert-basis). It measures on an average 0.20 7]wi. in height 

 and 0.25 mm. in basal diameter, and is constructed of thick 

 chitinous plates of irregularly polygonal shape, closely set to- 

 gether in a pavement-like manner ; the plates at the papillär 

 base are the largest and the deepest in color (brown). A small 

 pore {p, Fig. 576) opens at the apex of the cone, surrounded 

 by a circular area. No hook or spine is present on the intro- 

 vert ; nor can eye-spots be detected on the ganglion. The 

 tentacles are filamentous and are remarkably numerous, entirely 

 surrounding the mouth. 



