100 YEARS AGO

While walking along the main road on the outskirts of Bordighera yesterday morning, I noticed a strange-looking insect moving across it in a peculiar way. On getting nearer, I saw that what had attracted my notice was a black ant — about an inch long with brown wings — dragging a cricket bigger than itself... A low wall ran alongside the road, and when the ant got within six feet of it a common brown lizard appeared on the top of the wall and evidently soon caught sight of the ant, for it ran quickly down the wall and to within two feet of it, when it crouched for a second or two like a cat ready to spring, and then charged the ant, apparently butting the cricket free with its head. Before the ant could regain its hold the lizard seized the cricket in its mouth, and darted up the wall in the direction from which it originally appeared on the scene, leaving the ant running round and round, moving its wings in an agitated manner, vainly searching for its lost prey.

From Nature 22 October 1903.

50 YEARS AGO

Montegazza observed the survival of human spermatozoa after exposure to a temperature of –15 °C. He speculated that in the future, frozen semen might be used in animal husbandry and even proposed that a man dying on the battlefield might, by his wife, beget a legitimate child after his own death... Work in our laboratory, recently, indicated that treatment with 10 per cent glycerol prior to freezing with 'dry ice' produced an average 67 per cent survival of human spermatozoa obtained from five young healthy men... Three recipients have been successfully inseminated with frozen semen: one woman, nulliparous, has missed six menstrual periods, has cervical softening and uterine enlargement, and has developed other signs of pregnancy. The second woman, primiparous, has subjective signs of pregnancy, and one week after her first missed menses the Aschheim–Zondek test was suggestive; following an additional seven days of observation the test became positive. Five menses have not occurred. An X-ray film shows a normal developing foetal skeleton. The third recipient, nulliparous, has missed three menses and the Aschheim–Zondek test is positive.

From Nature 24 October 1953.