The Demon Breed by James H. Schmitz

Hardcover. Condition: Near Fine, Dust Jacket: Very Good+. 1968. Ace. Stock Image. Book Club Edition.

The bluish-grey torsos and powerful arms were enclosed by webbings of straps, holding tools and weapons. The bulging eyes on the big round heads were double-lensed..Seventy years before Parahuans came out of space to launch simultaneous attacks on a dozen worlds of the Hub. They lost the first round. Now they were back. And Nile had to stay alive long enough to get the message to the Federation's warships.