The Seeds from space are sentitent mobile tree-like vegetal lifefroms with articulated roots serving as legs and leaf-like appendages serving as arms and hands. They possess a pair of red eyes on top of their body. Specimens are known to have been seen on Earht in the 1930ies. In their own words:
"We are vegetables, in your language. Possibly trees, though we cannot be sure. Your books seem to describe only the lower orders of vegetable life. Possibly we are animals. When we had been through the small primers and others of your books we found the dictionary, which was most thorough and helpful. All three of us read this through page by page last night. Animals seem, according to the dictionary, to be many things - but active and sentient, as distinguished from vegetables. We are active and sentient, yet the pictures of animals seem quite different from us, and many of the vegetables look somewhat like us - so we are uncertain as to our status."
From "Seeds from Space" by Laurence Manning. Cover art by Frank R. Paul. Published in June 1935 Wonder Stories.