26 NEMERTINES OF PLYMOUTH SOUND. 
28. M. aurantraca, Grube. 
CEREBRATULUS AURANTIACUS, Hubrecht. 
One individual only has been obtained. This was found between 
tide-marks at Wembury Bay on June 10th. The length was only 
from 8 to 4.cm., the colour bright vermilion dorsally, ventrally pale 
pink. JDorsally the vermilion was interrupted on each side of the 
middle line over a region corresponding to the hinder quarter of the 
cephalic shits, in such a way as to cause the appearance of a neck, the 
pale unpigmented edges being almost invisible in comparison with 
the median strongly pigmented portion. ‘Two white patches were 
present, one on each side of the snout, of considerable vertical 
depth, as when the worm was examined laterally the white patches 
were seen to pass from the dorsal to the ventral lips of the cephalic 
slits. In the figure given by McIntosh of this species there is a 
single crescentic white patch, and the region in front of the crescent 
is pigmented like the body. In my specimen, however, not only is 
the patch double, but there is no pigmented region in front of it, the 
snout being anteriorly devoid of pigment. Eyes absent. Cephalic 
slits elongate and deep. 
No caudal appendage was observed in this individual. This was, 
curiously enough, the case in the specimen described by McIntosh, for 
though the caudal appendage was figured by the artist, the writer 
states that he did not himself observe it. 
Although many colour varieties of this species have been recorded, 
none, I believe, have been found with the anterior white patches dis- 
tributed in the way above described. 
This species is new to the British coast, not having been recorded 
further north than the island of Herm. 
29. M. Fascrouata, Hhrenberg. 
CEREBRATULUS FASCIOLATUS, Hubrecht. 
This very pretty species is common in the Sound, great numbers 
being dredged, especially at the Duke Rock. Many varieties of 
different shades of red have been collected, but no green varieties, 
which seem to be the most abundant at Naples. 
One specimen from the Duke Rock was interesting as an example 
of the regenerative power of this species. The whole animal was 
twice as long as its own cephalic slits; one transverse white band 
was present in the usual position of the first band, and accurately 
marked the middle of the animal. The head was of the size of that 
of a specimen of 3 or 4cm. Just before the posterior termination 
