50 Years Ago

One of the problems that continually faces electron microscopists is deciding whether organelles with the same fine structure have identical chemical composition and cellular function...does this apply to structurally simple organelles such as microtubules? Are they identical?

Microtubules...occur in specifically arranged aggregates in cilia, flagella, sperm tails and the mitotic spindle, but also occur free in the cytoplasm without any obvious pattern of arrangement. Surprisingly...despite all these proposed functions, it has generally been held that all microtubules are the same.

Now Behnke and Forer report that treatment of cranefly spermatids, rat sperm and rat tracheal cells with pepsin, colchicine, or storage at 0° C or 50° C clearly differentiate four classes of microtubules.

From Nature 22 July 1967

100 Years Ago

Fresh-water Wonders and How to Identify Them. By J. H. Crabtree.

The author of this little volume is an enthusiast on pond-life, and he seeks to introduce others to what has been to himself a world of wonder and beauty...It is a simple, unambitious book, but the author's standard of accuracy should have been higher. The amoeba does not “flit about”; the young “volvoces” do not occupy “the parent cell”; the bell-animalcule does not feed on smaller “hydrozoa”; nematodes are not Annelids, nor “segmented like the river-worm”...the fresh-water mussel does not feed ravenously on water-spiders...We are amazed at the easy-going way in which the author has tolerated numerous inaccuracies. It is not the way of science.

From Nature 19 July 1917 Footnote 1