600 eolididye. 



this species. He remarks that some Scottish specimens of 

 Eolis olivacea have the branchiae strongly banded with 

 brown ; and that in the young state it has very few 

 branchiae ranged in single or double series. 



23. E. AURANTiACA, Aider and Hancock. 



Ann. Nat. Hist. vol. ix. p. 34, and Monog. part 5, fara. 3, pi. 27. 



Body (half an inch long) lanceolate, tapering and 

 pointed behind, pale buff. Dorsal tentacles not very long, 

 a little wrinkled, tapering, tinged centrally with orange 

 red, their bases approximated ; oral tentacles rather 

 shorter, colourless, obtuse. Branchire linear-oblong, stout, 

 centrally red, terminally white, with an orange ring, ranged 

 in ten or eleven close lateral rows of from two to six 

 papilla?. Foot white, slightly lobed in front. 



Northumberland, Ayrshire, and Cornwall, in the lit- 

 toral and laminarian zones (A. and H.). The authors 

 of the monograph of " British Nudibranchiate Mollusca "" 

 suggest the probable identity of Eolis hellula of Loven 

 with this species. 



24. E. ciNGULATA, Aider and Hancock. 



{E. Histrix) Ann. Nat. Hist. vol. ix. p. 35, and Monog. fam. 3, plate 28. 



Body (three-eighths of an inch long) linear-lanceolate, 

 tapering and pointed behind, white variegated with olive 

 brown, especially along the sides. Dorsal tentacula long, 

 linear, smooth belted with olive below, and orange brown 

 above ; oral tentacles half as long, belted with orange 

 brown. Branchia; spindle-shaped, large, pale or olive, 

 belted with dark olive, and ranged in eight or more distant, 



