ANCULA. 77 



and has been got in Sweden by Professor Loven. The Doris 

 illuminata of Gould's ' Invertebrata of Massachusetts ' is also 

 probably this species. It is the P. modesta of Loven ; and the 

 young is the P. citrina of Alder. 



Genus VI. AN'CULA[*], Loven. 

 [PL III. f. 3.] 



Body limaciform, smooth : mantle indistinct or obsolete, 

 represented by a row of filaments on each side of the gills on 

 the middle of the back : dorsal tentacles laminated, non-retrac- 

 tile, with styliform basal appendages : oral tentacles consisting 

 of two tubercular processes on the sides of the head : odonto- 

 ■pliore narrow, with four spines in each transverse row : there 

 is a spinous buccal collar. 



Ancula differs from Polycera in having basal filaments on 

 the tentacles, as well as in the absence of a veil and mantle 

 or dorsal area. The same characters serve to distinguish it 

 from Idalia. It is founded on a single species. 



Ancula crista'ta, Alder. 



Polycera cristata, Alder in Ann. N. H. 1st ser. vi. p. 340, pi. 9. f. 10-12. 

 A, cristata, A. & H. Brit. Nud. Moll. fam. 1, pi. 25. 



Body nearly linear, a little swollen in the centre, and ter- 

 minating in a slender tail ; . white, with the processes tipped 

 with golden-yellow or orange : dorsal tentacles long, clavate, 

 and broadly laminated, the basal portion of each bearing two 

 styliform appendages : oral tentacles small, tubercular : gills 

 or branchial plumes 3, tripinnate, on each side of which is a 

 row of 5 linear appendages, tipped with yellow or orange. 

 L. 0-5. 



Habitat : This elegant species is found within tide-marks 

 and in shallow water on nearly all parts of the British coast. 

 In Ireland the only locality recorded is near Dublin (Alder) ; 

 but it will probably be found more common in that country 



[* A ministering goddess.] 



