First issued in 1913 and printed by Waterlow Brothers and Layton the Sea Horses were subsequently printed in 1915 by De La Rue and Co and again in 1918-19 by Bradbury,Wilkinson and Co. the original Waterlow plates were taken over by De La Rue and some re-working was done resulting in some variation in design details. One very visible difference are the lines behind the profile portrait of George V. Originally only horizontal, reworking added diagonal lines that appear in later printings. The issue at the top of the first illustration is the earliest printing of the stamp. As there were varieties caused by subsequent printings so too in colour. This becomes apparent when two examples of earlier and later printings are placed together. Originally sepia-brown later printings were yellow-brown and olive-brown. The details below show some of these re-engravings that are visible in the later issues.