POLYCERA. 577 



Body (sometimes nearly mu inch in length) lanceolate, 

 convex, smooth, white, occasionally marked with black, 

 and always variously lineated and spotted with golden 

 yellow, the spots in the back being tubercular. Tenta- 

 cula clavate, elongate, geniculated, broadly based ; lami- 

 nations of club nine or ten, yellow ; head veil ample, 

 with from four to six subulate processes, equal or un- 

 equal, and tipped with yellow. Eyes minute, closely 

 set at some distance above the tentacle bases. Branchial 

 plumes seven to nine, simply pinnate ; a single lateral ap- 

 pendage, stout, linear, and yellow-tipped on each side. 



This beautiful and very variable species is generally 

 diffused through the European seas, and has been taken 

 chiefly in the laminarian zone on all sides of Great 

 Britain and Ireland, often in considerable abundance. 



2. P. Lessonii, D'Orbigny. 



Polycera Lessonii, D'Orbigny, Mag. Zool. vol. vii. p. 5, pi. 105. — Alder and 

 Hancock, Monog. part 4, fam. 1, pi. 24. 

 „ citriiM, (young), Alder, Ann. Nat. Hist. vol. vi. p. 340, pi. 0, f. 7-0. 

 „ modesta, Lovkn, Ind. Moll. Scand. p. 6. 



Body (about half an inch in length, or more) lan- 

 ceolate-oblong, convex, greenish or yellowish, corrugated, 

 covered with scattered yellowish tubercles. Tentacula 

 subclavate, obtuse, ornamented with twelve or thirteen 

 laminations ; head-veil small, many-Iobed. Eyes very 

 minute. Branchial plumes three, small, bipinnate, green- 

 ish ; their lateral appendages tuberculated, subramose. 



Common in the coralline region, living on Gemellaria 

 loriculata on the Northumberland coast ; also found in 

 Dublin Bay (Alder). It inhabits the shores of France, 

 Sweden, and probably North-east America. 



VOL. III. 



4 £ 



