Obs. [CLOCK sb.3] An aquatic beetle.
1634. Moufet, Theat. Ins., I. xxiii. 164. Scarabei aquatici … quos … Germani Wasser kafers, Angli, Waterclocks appellant.
1681. Grew, Musæum, I. § vii. ii. 171. The Great English Waterclock. Hydrocantharus major Anglicus.
