I picked up a copy of 'Barlowe's Guide to Extraterrestrials' (1979; Workman Publishing Company, 146 pp) as a present to myself for Christmas 1979. It's a neat little paperback book that provides color illustrations of various aliens, taken from well-known SF works from the 30s to the 70s.
Along with some page scans (carefully) taken from my old and yellowing copy of the book, I've scanned a preview of the book that appeared in the December 1979 issue of Heavy Metal magazine.
The book's format gives each alien a two-page treatment. One page is a description of the physical characteristics, biology, and culture of the depicted alien, and may also provide illustrations of particular anatomical features of interest. The other page is a portrait of the alien as interpreted from the original literary source.
Along with the gallery of aliens (or ETs, as you may prefer), the book includes a folding three-page chart that allows for a comparison of the sizes of the various creatures:
The last 30-odd pages in the book are a gallery of sketches and preliminary drawings made by Barlowe in the course of preparing his final portraits.
Barlowe's artwork is meticulous, finely crafted, and well worth multiple viewings. Don't be surprised if the illustration of a particularly interesting alien creature leads you to search out the original novel it appeared in.
And, needless to say, it's always fun to see the ET from one of your favorite SF novels depicted in this book, particularly if the original image of it in your mind is a bit hazy and unformed.
One of the best examples is Barlowe's illustration of 'The Thing', from John W. Campbell's novelette 'Who Goes There ?' It certainly is more otherworldly than the creature portrayed by James Arness in the 1951 film, and it stands up to the creepy crawlies depicted in the John Carpenter film from 1982 and the Dark Horse comics from the 90s.
Copies of the paperback edition are readily available from amazon.com for very reasonable prices, so SF fans may want to get a copy of this entertaining book for their collections.