Description: English: Alder J. & Hancock A. (1845-1855). A monograph of the British nudibranchiate Mollusca: with figures of all the species. The Ray Society, London. Published in 8 parts:Part 3 Fam.3 Plate 31 [1847]. Alder & Hancock {Mon. Brit. Nud. Moll. (3) fam. 3, pi. 31) described the species Eolis arenicola which has never been found again, the single type specimen is lost, and the species thus remains dubious. It may or may not cover the species Egalvina viridula [now Eubranchus tricolor Forbes, 1838] Eolis northumbrica Alder & Hancock, 1844 synonym Diaphoreolis viridis (Forbes, 1840) accepted name. Date: 1847. Source:
https://www.biodiversitylibrary.org/item/131598#page/412/mode/1up. Author: Albany Hancock.
