The following is from an article in Impact No. 282:
The answer is no. This quote has been refuted by, for instance, creationist Marvin Lubenow.
Should Evolution Be Immune from Critical Analysis in the Science Classroom
by David Buckna and Denis Laidlaw
24. In 1982, Dr. Lyall Watson stated: "The fossils that decorate our family tree are so scarce that there are still more scientists than specimens. The remarkable fact is that all the physical evidence we have for human evolution can still be placed, with room to spare, inside a single coffin!" (Science Digest, vol. 90, May '82, p. 44.) Is Watson's statement still valid today?
It was true once, of course, but time marches on. It wasn't true by 1970. By 1982 we had (for instance) found, at Zhoukoudian alone, fragments from at least 40 individuals. By 1995 we had over 1,000 full or partial skeletons that are more than a million years old.