1877.] ANTHOBRANCHIATE NUDIBRANCHIATE MOLLUSCA. 239 
b. With but one pair of appendages near the branchie. 
3. ANCULA FUSCA. 
Drepania fusca, Lafont, Journ. de Conchyl. xxii. p. 369 (1874). 
Hab. 
Gen. Potycera, Cuvier, 1817. 
Themisto, Oken, 1815 (part of); Cuf@ea, Leach, 1820; Polycere, 
Risso, 1826; Polycerus, Verany, 1846. 
Body limaciform. Mantle indistinct, forming a supracapital veil, 
and a tuberculate ridge on the sides. Rhinophores laminated. Bran- 
chiz non-retractile, with lateral appendages. Odontophore with 
twelve to sixteen plates in each transverse row, the two near the 
centre large and bicuspid ; nocentral spine. Lateral corneous jaws. 
Messrs. Alder and Harcock classify the species under two well- 
marked divisions. 
a, Supracapital veil dilated, with the margin bearing tentacular 
Jjilaments. Branchie simply pinnate; their lateral appen- 
dages elongated and few. 
1. P. QUADRILINEATA, Sars. 
Doris quadrilineata, Miiller, Zool. Dan. Prod. p. 229 (1776). 
D. cornuta, Abildg.; D. flava, Mont.; Themisto quadrilineata, 
Oken; 7. flava, id.; Cufea flava, Leach; Polycere flava, Risso ; 
Polycera flava, Fleming ; ? P. varians, Sars; P.ornata, D’Orb.; P. 
typica, Thompson; P. cornuta, Lovén. 
Hab. North and south European coasts. 
2. P. norripA, Hesse, Journ. de Conch. xx. p. 345 (1870) ; 
figured, xxi. pl. 12. f. 1, 2. 
Hab. French coast. 
3. P. prepesa, Lovén, Ind. Moll. Scand. p. 6 (1846). 
Hab. West Scandinavian shores. 
b. Supracapital veil short, bilobed, the margin tuberculate. Bran- 
chie plumose, their lateral appendages tubercular and more 
numerous. 
4. P. ocetuata, Ald. & Hane. Ann. & Mag. Nat. Hist. ix. 
p. 33 (1842). 
? Triopa nothus, Johnston; P. (Palio) ocellata, Moreh. 
Hab. North European coasts. 
5. P. ressonu, D’Orbigny, Mag. de Zool. vii. p. 5, pl. 105 (1837). 
P. citrina, Alder ; Doris illuminata, Gould ; P. modesta, Lovén ; 
Aigires lessonii, Gray ; P. illuminata, Stimpson. 
Hab. North European coast, and Eastern North America (Massa- 
chusetts). 
6. P. pupica, Loven, Ll. c. p. 6. 
Hab. West Scandinavian shores. 
