332 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 
but having long narrow posterior processes, and usually sense organs 
in the form of knobs studded with bristles and set round the mouth ; 
Navarehus' (Cooper), in which the front margin of the anterior shield 
is developed into rhinophore-like projections. Bergh admits that 
Navarchus is a somewhat doubtful genus, and one of my specimens of 
Chelidonura varians exhibited tentacular projections of the anterior 
shield which were absent in the other examples. It remains to be 
seen whether the distinction in shape between Doridium and Chelido- 
nura is absolute, or whether intermediate forms will be discovered. 
Dorrprum.—About fourteen species seem to be known with more 
or less certainty, of which two are now described for the first time. 
1. D. tricoloratum (Renier). Mediterranean. 
2. D. depictum (Renier). Mediterranean. 
3. D. punctilucens, Bergh. W. Indies. 
4. D. purpureum, Bergh. California. 
5. D. eylindricum (Cheeseman). New Zealand. 
6 
a 
8 
. D. ocelligerum, Bergh. N. Pacifie. 
. D. diomedium, Bergh. N. Pacitic. 
. D. lineolatum (H. & A. Adams). Pacific. 
9. D. alboventrale, Bergh. Malay Archipelago. 
10. D. eyaneum, Martens. E. Africa. 
11. D. obscurum, Bergh. S. Pacific. 
12. D. Pilsbryi, Eliot. 8S. Pacific. 
13. D. Gardineri, Eliot, n.sp. 8. Pacific. 
14. D. reticulatum, Eliot, n.sp. KE. Africa. 
Doripium GARDINERI, NOV. sp. 
Four specimens captured by Mr. Stanley Gardiner at Rotuma. The 
length of the largest is 51 mm., the breadth 25mm. The head-shield, 
which is 23 mm., has ample mar gins and a free flap behind measuring 
6mm. The edges of the posterior shield are also more distinct than 
usual. The pare rapodia are ample, the free part at the sides measuring 
11 and that behind 14mm. The posterior shield is prolonged into two 
voluminous processes, which do not form a dise but le hke the tails 
of an evening coat. Each is folded on itself, and thus double. 
A fleshy prominence proceeds from the left process towards the 
right, and takes part in covering the gill. The exposed parts of the 
two larger specimens are of a uniform deep bluish black, and 
the inside of the parapodia silvery grey. The two smaller specimens 
(which, however, have the specific characteristics) are brownish and 
lighter at the sides. Mr. Gardiner’s note as to the colour of the 
living animal is almost obliterated by the action of the alcohol, 
but appears to read ‘Black . . . yellow . . . at sides. 
This may refer to the brownish specimens, or possibly to two distinct 
yellowish rhinophorial organs situated on the upper part of each 
side of the head below the edge of the shield. They are about 10mm. 
long, and consist of a series of lamin arranged in almost pinnate form 
but the central axis is not continuous, The gill is posterior, yellowish 
' Pilsbry calls Navarchus, Navanac. 
