Morgan Dennis....1892-1960 Known as an Illustrator and Etcher. In my old Davenports he has one sale at auction back in 1994 of a 10x 14 piece for $660.00
Go to
WWW.askart.com. unfortuantely it's not a free service...for value..current auction records...
Auction records rather than gallery sales determine what an artists work is really worth. Also having auction records legitimizes an artist...
Your piece has an indented line around it right...it's real....when they press the plate against the paper to creat the image it indents the paper...Then it's signed and usually numbered by the artist.
I would get the thing rematted with acid free matting to protect the piece from any further deterioration...
You have a nice piece that has some value...It probably was commissioned by the owner of the dog as a memorial.
I wouldn't worrk too much about the pieces authenticity..it's not really worth enough for a forger or faker to play around with...now if it were a Picasso I would start to wonder...