MOLLUSCA. 87 



varieties are found on the zoophytes in the fishing-boats. 

 Occasionally in the stomach of the cod. 



Tritonia plebeia, Johnston ; A. & H. B. Nud. M. fam 2 



pi. 3. ' 



In vast numbers amongst the zoophytes from deep water, 

 m the crevices of Alcyonium digitatimi and on Hahcuim 

 tossed ashore after storms. One specimen showed the abnorm- 

 ality of a bifid tail (Plate II. fig. 15). 



Suborder III. ACANTHOBRANCHIATA. 

 Fam. 1. Polyceridae. 

 Genus 1. ^GiRUS, Lovdn. 



jEgirus punctilmens, D'Orbigny ; A. & H. B. Nud. M. 

 fam. 1, pi. 21. 



ISlot uncommon under stones in rock-pools between tide- 

 marks at the East Rocks. 



Genus 2. Triopa, Johnston. 



Triojia claviger, Muller ; A. & H. B. Nud. M. fam 1 

 pi. 20. ' 



Fine specimens are occasionaUy found under stones near 

 low-water mark. The same Ergasilus is parasitic on this as 

 on Doris. 



Genus 5. Polycera, Cuvier. 



Polycera quadrilineata, Miiller ; A. & H. B. Nud. M 

 fam. 1, pi. 22. 



Not uncommon near low-water mark and in the laminarian 

 region. 



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 Eocks. 



