I believe this was a 50's or early 60's sci-fi movie which had elephant trunked, turtle like aliens that crawled along the ground and latched on to people and animals to suck dry!
The title eludes me, can't seem to find on any lists.

Possibly Island of Terror (1966) (http://www.imdb.com/title/tt0060548/synopsis)?

Island of Terror, 1966, with Peter Cushing

"Island of Terror" (1966) .
The creatures were called "Silicate" monsters.


http://2.bp.blogspot.com/_v0fV15P7uQo/RlA1zcLeIYI/AAAAAAAAAmY/9i4_oFzQZqU/s400/shortside.jpg