50 years ago

It is well known that various organisms can be cooled to very low temperatures in liquid gases without injury, provided that they have previously been desiccated to some extent. Extracellular freezing is considered to be a mode of dehydrating living cells; and some organisms, at least frost-resistant ones, may withstand freezing of this type even at very low temperatures ... Our experiments show that, after sufficient extracellular freezing, an intact insect can be kept alive at an extremely low temperature without any antifreeze agent. We used a 'slug caterpillar', Cnidocampa flavescens (Walk.) in the overwintering prepupal stage ... [T]he larvae in their cocoons were first frozen in a special refrigerator, in which the air temperature was lowered from −5° to −90 °C. in 1½ hr. and maintained at that temperature for 45 min. The insects were then rewarmed in air at room temperature. After thawing, about one-third of the sixty larvae revived.

From Nature 2 August 1958.

100 years ago

Mr C. Kenrick Gibbons has presented to the Zoological Gardens a large number of the small fresh-water fish from Barbados known as “millions” (Girardinus poecilloides). These little fish, which have been placed in a tank in the tortoise house, are of special interest because of their supposed action in preventing malaria. Malaria is very much less common in Barbados than in other West Indian Islands, and it has been suggested that this freedom is due to the presence of enormous quantities of the “millions” in the fresh-water pools. The little fish are very voracious, and destroy large numbers of the larvae of mosquitoes that spread malaria ... It is understood that experiments are going to be made with the introduction of these fish into tropical countries where malaria is prevalent.

From Nature 30 July 1908.