Looking at the section previewed through Google Books, I couldn't help feeling that it seemed a little... familiar. Take a look at this screenshot from Google Books:
Now take a look at this screenshot, taking from a page written by my erstwhile associates at Palaeos.com, last modified in 2006:
I can only go by what was available in the Google Books preview, of course, without direct access to the actual book, but I can confirm that most if not all of the material in pages 15 to 72 at least of the "Anatomy of Mollusca" appears to have been copied directly from Palaeos.com (unfortunately, a large part of Palaeos.com is currently offline as the site gets revamped). A quick Google search failed to uncover anything indicating whether the International Scientific Publishing Agency has a reputation for publishing lifted material, so I can't say if this is part of a broader issue.
Amazon currently has the "Anatomy of Mollusca" on sale for just over $75. Not that expensive by the standards of technical publications, but a fair chunk of change by the standards of books in general. Certainly a lot more than the cost of reading the same stuff on Palaeos.com, which carries no extra cost beyond that of the ISP charges.