112 CATALOGUE OF THE MOLLUSCA 
Among the rocks near low-water mark ; not rare. Cullercoats 
and Whitley. 
3. P. Lesson, D’Orb. 
Polycera Lessonii, D’Orb. in Mag. de Zool. vii. 5, t. 105. 
Polycera citrina, Alder in Ann. Nat. Hist. vi. 340, t. 9, 
18 (sR 
On Gemellaria loriculata, in from 15 to 20 fathoms water ; 
common. Cullercoats—J. A. and A. H. Whitburn.—M~. R. 
Howse. 
9. ANCULA, Lovén. 
1. A. cristata, Alder. 
Polycera cristata, Ald. in Ann. Nat. Hist. vi. 340, t. 9, f. 
100 
Ancula cristata, Ald. and Hanc. Mon. Nudib. Moll., fam. 1, 
pl. 25. 
Among the rocks at Cullercoats and Whitley ; common. 
Newbiggin.—J. A. Marsden.—A.H. Holy Island —Dr. John-- 
ston. 
10. IDALIA, Leuckart. 
1. I. aspersa, Ald. and Hane. 
Idalia aspersa, Ald. and Hance. Mon. Nudib. Moll., fam. 1, 
pl. 26. 
One specimen found on Fusus antiquus from the fishing boats, 
Cullercoats.—J. A. 
2. I. evecans, Leuck. ? 
Body convex, white, tinged with flesh colour ; tentacles long 
and slender, with 4 long tentacular filaments in front, 2 at the 
base of each tentacle ; lateral filaments 6 on each side, very long, 
the last bifid: there are also 3 rows of filaments on the back ; 
the central one containing 3, the sub-lateral ones 5 each. Bran- 
chi, consisting of 11 slender pinnate plumes, largest in front, 
and becoming very small behind; the anterior plume is bifid. 
Length, half an inch. 
An individual of this species was obtained by the Rev. G. C. 
Abbes from the fishing boats at Whitburn. It is similar to a 
specimen from Torbay, preserved in the British Museum, and 
labelled Idalia elegans, by Dr. Leach. There may be some 
