580 DORIDID.E. 



Two examples of this beautiful sea-slug, nearly allied to 

 the last, but presenting distinct characters in the propor- 

 tions and disposition of the tentacular and branchial 

 appendages were dredged in thirty-five fathoms water on 

 a sandy bottom in St. Magnus Bay, Zetland (M' Andrew 

 and E. F.). When kept they appeared to be sluggish, 

 and are very glutinous to the touch. 



3. I. QUADRicoRNis, Moutagu. 



Lin. Trans, vol. xi. p. 17, pi. 14, fig. 4. 



" Body ovate, mottled brown and white ; along each 

 side an obsolete row of tubercles, somewhat dilatable, 

 extending from the tentacula to the vent ; tentacula four, 

 long, both pairs originating from the upper part, and 

 approximating ; the anterior shortest, setiform, inclining 

 forwards ; the others filiform, reflecting backwards, the 

 same colour as the body ; vent .situated near the extremity 

 of the back, surrounded by eight or nine branched append- 

 ages. Length three-eighths of an inch/"' (Montagu) 

 Devon. 



ANCULA, Lov^N. 



Body elongated, smooth, a semicircle of simple filaments 

 or clavate processes bordering the branchial region of the 

 back. Tentacula clavate, laminated with filiform appen- 

 dages on their stalks. No capital veil. Vent dorsal, sur- 

 rounded by plumose branchiae. 



A, CRIST AT A, Alder. 



Plate Z. Z. fig. 4. 

 Polycera cristata, Aldek, Ann. Nat. Hist. vol. vi. p. 340, pi. 9, f. 10-12. 

 Ancula cristata, LovilN, Ind. Moll. Scand. p. 5. — Alder and Hancock, Monog. 

 part .3, fam. 1 , pi. 25. 



Body half an inch long, convex, lanceolate, tapering be- 

 hind, translucent white, smooth, bearing on the central and 



