56 COE 



The intestinal caecum is enormously developed. Its diverticula 

 reach forward on each side even to the anterior end of the brain. In 

 the brain region each of the caecal diverticula appears as a rounded lobe 

 on either side directly above, and closely approximating to, the dorsal 

 brain-lobe. Back of the brain there are several rather slender lobes 

 on each side. These lie mainly above the lateral nerves, but send off 

 branches below the nerves at frequent intervals. Somewhat farther 

 back in the esophagal region these lateral lobes join the main, un- 

 paired caecum, which lies immediately below the esophagus. This 

 caecum, throughout its course to the intestine proper, gives off nu- 

 merous lateral diverticula on each side, and these branch upward 

 above the lateral nerve cords (pi. xi, fig. 3). 



Sub-muscular glands. These occur abundantly in the brain region, 

 and are still more closely packed together in the anterior portion of 

 the esophagal region. They occupy positions, as in other species, in 

 the connective tissues beneath the musculature in the latero-ventral 

 regions of the body. Each gland is composed of a number of cells, 

 and each has a duct leading through the layers of the body wall to the 

 exterior on the latero-ventral aspect. A much smaller number open 

 on the dorsal surface. In the posterior end of the esophagal region 

 these glands have almost entirely disappeared, although a few are met 

 with in the anterior portion of the intestinal region. 



Color. The color of the individuals of this species is commonly a 

 homogeneous, opaque white, very pale flesh color, or pale yellowish- 

 white. This color is continuous throughout the length of the body, 

 both above and below, except where the internal organs show through. 

 The smaller specimens are pale, while the larger ones almost always 

 exhibit a brownish color, which indicates the position of the intestine. 

 Sometimes minute reddish-brown specks are distributed over the dorsal 

 surface. Occasionally a worm of this species is met with in which 

 the intestinal lobes are pale orange. The brain is plainly distinguish- 

 able in the living worm because of its pinkish coloration. 



Habitat. Amphiporus exilis is one of the most common, as well 

 as the most widely distributed species of nemerteans met with on the 

 expedition. It occurred abundantly at nearly all the collecting stations 

 from Victoria, B.C., to Dutch Harbor, Unalaska. The worms are 

 restless and are often seen crawling over stones between tides. They 

 live among barnacles, mussels, etc., from low water well up to high 

 water mark, and are found abundantly under stones in almost all sorts 

 of locations. The species is especially hardy. 



