70 POLYCERIDiE, 



oral tentacles indistinct : gills plumose, partially surrounding 

 the vent (which is on the median line), non-retractile : mouth 

 with a broad spinous tongue and an upper corneous jaw. 



This genus contains only one known species. 



^GiRUs puNCTiLu'cENS, D^Orbigny. 



Polycera punctilucens, D'Orb. in Mag. de Zool. vii. p. 7, pi. 106. M. 

 punctilucens, A. & H. Brit. Nud. Moll. fam. 1, pi. 21. 



Body stout, rather elevated in the centre of the back, and 

 tapering behind, purple-brown, sprinkled with white and 

 darker brown spots, and covered with large, obtuse, cylindrical 

 or subclavate tubercles ; interspersed between these are several 

 circular velvety-brown areas containing each a central bril- 

 liant greenish-blue gem-like spot, with a circle of dark brown 

 spots surrounding the area : dorsal tentacles linear, smooth, 

 and obtuse, with two or three reddish-brown bands; they 

 issue from sheaths surmounted by five large conical lobes: 

 oral tentacles indistinct: gills or branchial plumes 3, large, 

 tripinnate, whitish, in front of which are 3 large, branched, 

 tubercular processes. L. 0*75. 



Habitat : Under stones among rocks near low-water mark : 

 rare, but pretty generally diffused. It was first obtained on 

 our coasts near Campbeltown, in Argyleshire, by Professor E. 

 Forbes, who published it under the name of Doris Maura, 

 unaware that it had been previously described by D'Orbigny. 

 Other localities are, Courtmasheny Harbour, Ireland ( Allman) ; 

 Ardrossan and Lamlash (Alder) ; Burghead (Murray) ; near 

 Fowey, Cornwall (Peach), [Falmouth (Cocks)]; and CuUer- 

 coats, Northumberland (Norman). Abroad it has been got by 

 D'Orbigny in the harbour of Brest, [by Aucapitaine and others 

 in the west of France,] and on the Swedish coast by Professor 

 Loven. 



This very curious moUusk appears at first sight rather unat- 

 tractive ; but on nearer inspection the briUiant gem-like spots 

 give it a very elegant and peculiar appearance. 



