172 



WILSON. 



[Vol. I. 



lae and the intervals on the ventral surface, up to within i mm. 

 of the mid-line, are filled in with ordinary large papillae. 



Proboscis large, 3-6 cm. long and 1-3 cm. wide. It is capa- 

 ble of being extended to 12 cm, with a corresponding dimi- 

 nution of its width. It is cylindrical at the base, but quickly 

 opens into a half tube which is broadened at the tip into a 

 shovel form (Fig. i). The exterior is a brighter yellow than 

 the body and perfectly smooth. The interior is rich orange 

 and completely ciliated, but in most specimens examined it 

 lacks the longitudinal brown stripes noted by Greef in E. Pal- 

 lasii (6). In several specimens, however, they showed up 

 faintly against the orange background. 



The skin also on the interior of the proboscis is thrown up 

 into longitudinal ridges, the intervening furrows between which 

 are darker in color than the ridges themselves (Fig. 3). The 

 mouth opens through the center of the cylindrical base. A 

 well-defined ridge runs outward from the mouth along the 

 dorsal mid-line toward the tip of the proboscis. This ridge is 

 somewhat brighter in color than the rest of the interior, but is 

 completely concealed unless the proboscis is opened. The tip 

 of the proboscis sometimes has a well-marked chocolate-brown 

 edge. 



The ventral nerve cord and blood vessel show plainly through 

 the skin {cf. Figs, i and 2), and when the body is extended the 

 dark-colored intestine can be seen at points where it touches the 

 inner surface of the body walls. The sexes are alike externally, 

 with no appreciable difference in size (cf. Figs, i and 2). 



But when sexually ripe, Greef says that the golden eggs or 

 the white semen in the nephridia show through the body wall 

 enough to distinguish the males from the females (6). 



Internal Morphology like that of all echiuroids. The alimen- 

 tary canal is several times the length of the body and is looped 

 irregularly. It is suspended from the body walls by thin mus- 

 cular strands instead of a continuous mesentery, and upon the 

 slightest perforation of the body walls it is extruded through 

 the orifice by a violent contraction of the muscles. 



This alimentary canal may be divided into three regions or 

 parts, called respectively the fore, mid, and hind gut. 



