irregular rings, and the bases set a little apart. Oral tentacles as long as the dorsal ones,
and like them abruptly truncated and white at the extremities. Branchm suhclavate, and
of a cold bluish green with white tip s; the coloured vessel is granular, and does not entirely
fill the sheaths. They are set in nine transverse rows, far apart from each other, and
divided down the back: the three anterior rows are nearer together than the rest. The first
and second rows have three papillae each, the third five, and the two or three following four
each; the rest gradually diminishing towards the tail. From the transparency of the skin a
green internal fine is visible down the back, marking the direction of the central vessel
of the digestive system, from which branches are seen going off into the papillse; there is
also a darkish lozenge-shaped spot immediately in front of the dorsal tentacles. Foot
extending a little way further than the termination of the branchiae behind; the anterior
angles not much produced and somewhat rounded.
A single specimen only of this species has been obtained, but as it lived several days
with us, we were enabled to complete a careful drawing and description. I t approaches
very near to the Montagna viridis of Forbes, but differs in the character of the dorsal
tentacles and branchial papillae. In B. Northumbrica the former are linear, and have the
upper portion annularly wrinkled or ringed, which gives them the appearance of swelling a
little towards the tip. In B. viridis these organs taper gradually, and are without rings or
wrinkles. The papillae of B. Northumbrica are of a much darker colour, less granular, considerably
larger, and are carried more erect, and in a radiating manner, whilst in ,B. viridis
they incline more backwards in the usual way, are nearly linear or, slightly elliptical, and
taper at the points. The differences between this and B. am ten a have been already pointed
out in our description of that species.