386 ^OLiD^. 



of the foot tentaculiform ; jaw with a single row of denticles. 

 Radula consisting of one row of plates, their edge serrulate. 

 Penis without hooks. H. opalescens, Cooper, California. 



^OLiDiA, Cuvier. 



Syn. — ^olidiana, Quatr. Cavolina, Brug., Orb. Montagua, 

 Flem. 



Distr. — 4 sp. European seas. jE. annulata^ Quoy (xci, 31). 



Rhinophores (upper tentacles) simple; the papillae compressed, 

 in transverse, rather distant rows ; anterior angles of the foot 

 almost rounded; middle projecting piece of the jaw not den- 

 ticulated. Spawn of one or two coils. 



^OLiDELLA, Bergh. 



Distr. — 4 sp. Europe. 



Form of the body, tentacles and papillae like those of J^olis; 

 masticatory edge of the jaw minutely plaited ; teeth of the 

 radula in one row, comb-like, notched in the middle. 



Flabellina, Cuvier. 



Distr. — 6 sp. Mediterranean, Fhillipines. F. coronata, Forbes. 



Body slender, rhinophores perfoliate ; tentacles elongated ; 

 dorsal papillae on compressed stalks ; foot angularly produced 

 in front ; jaws minutely toothed-margined ; radula uniserial. 

 Spawn multispiral 



Pter^olidia, Bergh. 



Distr. — 1 sp. P. Semperi, Bergh. 



Rhinophores perfoliate ; lower tentacles elongated ; dorsal 

 papillae not caducous, on wing-like, compressed pediments; ante- 

 rior margin of foot inflated, tentacularly produced at the sides ; 

 jaws toothed ; radula uniseriate ; penis unarmed. 



Cratena, Bergh. 



Syn. — Cavolina, Brug., part. Example. — C. hirsuta, Bergh. 



Rhinophores simple ; anterior angles of the foot rounded ; 

 middle part of the jaw minutely denticulated. Spawn arranged 

 in one or two coils. 



GoNi^OLis, Sars. 



Distr. — 1 sp. Norway. 



Animal with a distinct mantle-border, which gives a square 

 form to the body ; tentacles not retractile, dorsal veiy large, 

 labial placed at the sides of a large velum ; dorsal papillae simple, 

 scattered on both sides of the back. 



RizzoLiA, Trinchese. 

 Example. — R. pereg?Hna^ Gmelin. 

 Near Cratena and Facelina by the dorsal appendages being 



