THE NEMERTINES OF MILLPORT AND ITS VICINITY. 7 
MacInrosu’s description (10) of C. linearis gives the length as three to four inches. 
The colour is stated to be variable; the animals are said to be in general of a pale 
cream tint, which is sometimes diversified by a yellowish patch on the snout and a 
yellowish tinge in the cesophageal region; or the pigment—yellowish, orange, or 
reddish—of the snout may be increased towards its tip, the cesophageal region being 
also in such cases of a reddish orange colour. There are said to be no eyes; and the 
red pigment at the anterior end is stated to be of no specific value. In the specimen 
represented in this author’s pl. iv. fig. 5 (the posterior part of the specimen being green), 
the reddish pigment of the snout is shown as extending farther back laterally than in 
the middle line. Nothing is said in the text as to the aggregation of the pigment in 
granules. 
JOUBIN (8) describes separately the forms with red anterior tip as C. bioculata. He 
states that in these the head is red, the red colour increasing in depth towards the tip 
of the snout; the pigment occurs in the form of minute granules; the two eyes, con- 
stituted perhaps by the agglomeration of minute ocelli, are of considerable size, on the 
extreme margin, and placed among the red pigment grains. The same author (7) 
speaks of the presence of two “oculiform points,” which may or may not be capable of 
resolution into a number of small eyes, as the feature which distinguishes C. bioculata 
from C. linearis ; C. bioculata is also said to be shorter than C. linearis. 
Burcer (3), also describing C. linearis and C. bioculata separately, states that the 
single specimen of C. linearis met with at Naples had no eyes, nor pigment of any kind 
in the head. C. beoculata is said to be three to four cm. long, and to be colourless or 
whitish with the exception of two very small bright red spots at the end of the head ; 
with weak magnification, there is visible at the anterior border of the head a small black 
pigment spot, which, however, may not be an eye ; and immediately behind this are two 
larger, sharply defined, round reddish spots in which ccerulean-blue pigment is inter- 
spersed. It is difficult to see much of this in the corresponding figure, which, being on 
a small scale, does not even show the separation of the red areas of the two sides. 
BurceER compares his specimens of C. bioculata with those of MacInrosu’s specimens 
(of C. linearis) which possessed the red pigment; he considers the two to be the same 
form, though he recognises that MacInrosu’s specimens showed a more diffuse dis- 
tribution of the pigment than those found by him at Naples. 
In the Trerreich (5), BURGER defines C. linearis as being white, often with a yellow 
tinge, as having no pigment spots, and as being 100-150 mm. in length. C. rufifrons 
( = bioculata), on the other hand, is whitish, with two small red-blue pigment spots at 
the end of the head, and is 30-40 mm. in length. 
The forms about to be described are common at Millport, and may often be found 
under stones between tide levels. When extended they are filiform, and from two to 
three inches (50-75 mm.) in length; the proboscidean apparatus extends about one- 
third to two-fifths of the length of the animal; the distance between brain and 
mouth is about three times that between anterior end and brain, Since the union of 
