Grady Louis McMurtry was born 1918 so a bit too old for beeing the Zodiac.

However this is quite interesting:

http://www.parareligion.ch/rf/rf5.htm

" This ‘squiggle’ that Grady
draws in the letter for Crowley is (see Fig.1) one which he further
states contains a great deal of mystical meaning." Grady writes a whole
paragraph about this symbol and further elaborates that he’d like "to
make a seal ring. I am thinking of having a design such as this (see
Fig.2) cut on it. Thus I would have the feather of Thoth-Maat at the
prow and the hawk of Horus at the helm, with the sun and the star
representing Hadit and Nuit." In the future he would occasionally use
this symbol as his signature at the bottom of some letters. Grady also
drew this symbol in green pencil in the center of a small tombstone
which has a tiny little worm crawling across the top. (see Fig.3) This
drawing is located on the top of an original typed copy of one of his
undated poems, A Worm in Earnest. The drawing might imply that the
"little worm who burrows, burrows" is crawling across the top of
Grady’s own tombstone.