Allen is the original X-man. It's a fascinating story about how it all started, but his oeuvre was all about X's. In this particular painting, the X is a bit disguised, but powerful none the less.
Researching him is well worth your while.
Image is from and more images at
Williams Gallery, New Zealand.
And 20 more images at the
Gow Langsford Gallery,
also in New Zealand.