Mollusca of St. Andrews. 431 



Polycera ocellata, Alder & Hancock ; A. & H. B. Nud. M. 

 fam. 1, pi. 23. 



Gregarious under stones between tide-marks, but not com- 

 mon. They chiefly occur at the West Rocks. 



Polycera Lessoni, D'Orbigny ; A. & H. B. Nud. M. fam. 1, 



pi. 24. 



On a laminarian blade after an October storm j one spe- 

 cimen. 



Genus 6. Ancula, Lov^n. 

 AncuJa crisfata, Alder ; A. & H. B. Nud. M. fam. 1, pi. 25. 



Not rare under stones in rock-pools, chiefly at the East 

 Rocks. 



Genus 8. Goniodoris, Forbes. 



Gomodoris nodosa, Mont. ; A. & H. B. Nud. M. fam. 1, 

 pi. 18. 



Abundant between tide-marks under stones in rock-pools 

 and elsewhere, throughout the year. 



Fam. 2. Dorididae. 



Genus Doris, L. 



Doris tuberculata, Cuvier ; A. & H. B. Nud. M. fam. 1, pi. 3. 



Abundant under rocky ledges and under stones in pools. 

 Its parasite, Ergasilus, is common. 



Doris Johnstoniy Alder & Hancock ; A. & H. B. Nud. M. 

 fam. 1, pi. 5. 



Occasionally under stones in pools between tide-marks at 

 the East Rocks. The same Ergasilus occurs on this species. 



Doris repanda, Alder & Hancock ; A. & H. B. Nud. M. 

 fam. 1, pi. 6. 



Abundant at all seasons amongst the rocks between tide- 

 marks. 



Doris asperttj Alder & Hancock ; A. & H. B. Nud. M. fam. 1, 

 pi. 9. f. 1-9. 



Common under stones in pools near low-water mark. 



