NEMERTEANS 



145 



Size. Length of largest specimen obtained 45 cm.; width 4-6 

 mm. ; usual length 10-20 cm. 



Color. The colors are far less opaque than in most species, and 

 are of such a nature as to give the tissues a remarkably translucent ap- 

 pearance. Anterior portion of body pale orange inclining to flesh 

 color, sometimes more decidedly orange and sometimes pale flesh 

 color. Head distinctly orange, but usually of a pale tint. Brain re- 

 gion a little more reddish in color. General color of intestinal region 

 grayish flesh color, or very pale salmon, and somewhat translucent, 

 but this ground color is so much obscured by the dark green color of 

 the intestinal tract that in effect this region appears of a greenish tinge. 

 Commonly the green color extends as a pair of broad, irregular longi- 

 tudinal bands separated by a pale reddish median band (where the in- 

 testinal lobes do not show) , and bordered on the lateral margins by 

 pale, grayish salmon or occasionally by whitish. 



The ventral surface is somewhat paler than the dorsal, and the 

 median reddish band is replaced by the greenish color of the intestine. 



On the dorsal surface near the anterior end of the body are two 

 regions of slightly differentiated color, the one reaching back in the 

 median line nearly to the brain, the other extending about as far pos- 

 teriorly behind the brain as is this organ from the tip of the snout. 

 These show simply as regions of more orange color, and the posterior 

 region is separated from the flesh colored portion behind by a V- 

 shaped, orange colored groove. The apex of the groove lies in the 

 median line and points posteriorly, while its limbs extend obliquely 

 antero-laterally to the ventral surface where they come nearly into 

 contact in the median line. A similar, but very indistinct, V-shaped 

 groove lies just posterior to the anterior orange colored region. 



On the under side of the head is a pale area on the tip of the snout 

 marked off posteriorly by an orange colored line from the still paler 

 triangular area found on each lateral side of the head. 



About 10-15 mm. back of the head (in an individual about 20 cm. 

 long) darker areas appear on the sides of the body and increase in 

 number back to the intestinal region. These indicate the pouches of 

 the intestinal ca3ca which stretch forward far into the esophageal region, 

 and which in the intestinal region are dark green in color. This color 

 is very permanent and remains after preservation in formalin or in 

 alcohol, and even after imbedding in paraffin. The green intestinal 

 lobes nearly all fork distally, and each fork is again divided, but there 

 is much irregularity in this respect. 



The median dorsal band of pale reddish color is due to the color of 



.V' 



