20 



mass of ice, and Eeaumur relates many similar instances." Later on, pages 452-3 of the same 

 volume, in treating of hibernation of insects, I find the following very interesting remarks : 

 " But though many larvte and pupse are able to resist a great degree of cold, when it in- 

 creases to a certain extent they yield to its intensity and become solid masses of ice. In 

 this state we should think it impossible that they should ever revive. That an animal 

 whose juices^ muscles and whole body have been subjected to a process which splits bomb- 

 shells and converted into an icy mass that may be snapped asunder like a piece of glass, 

 should ever recover its vital powers, seems at first view little less than a miracle, and if the 

 reviviscency of the wheel animal ( Vorticella rotatoria) and of snails, etc,, after years of 

 desiccation had not made us familiar with similar prodigies, might have been pronounced 

 impossible, and it is probable that many insects when thus frozen never do revive. Of 

 the fact, however, as to several species, there is no doubt. It was first noticed by Lister, 

 who relates that he had found caterpillars so frozen that when dropped into a glass they 

 clinked like stones, which nevertheless revived. Reaumur, indeed, repeated this experi- 

 ment without success, and found that when the larvae of Bombyx Pityocampa, F. were 

 frozen into ice by a cold of 15" R. below zero (2" F. below zero) they could not be made 

 to revive. But other trials have fully confirmed Lister's observations. My friend, Mr. 

 Stickney, the author of a valuable " Essay on the Grub " (larva of Tipula oleracea) to 

 ascertain the effect of cold in destroying this insect, exposed some of them to a severe 

 frost, which congealed them into perfect masses of ice. When broken, their whole interior 

 was found to be frozen. Yet several of these resumed their active powers. Bonnet had 

 precisely the same result with the pupae of Papilio hrassicce, which, by exposing to a frost 

 of 14° R. below zero (0'' F.), became lumps of ice and yet produced butterflies. Indeed, 

 the circumstance that animals of a much more complex organization than insects, namely, 

 serpents and fishes, have been known to revive after being frozen is suflficient to dispel any 

 doubts on this head." In Burmeister's " Manual of Entomology " the above instances 

 are also referred to though at much less length, but as no additional facts are adduced it is 

 unnecessary to quote from his work. 



The above would seem sufficient to establish the proposition that some insects can 

 survive freezing, and indeed when one remembers that insects successfully maintain their 

 existence in the most arctic lands which have ever been visited by man, it seems strange 

 that any one should ever have questioned it. Is it conceivable that these tiny crea+ures, 

 when in a state of lethargy and partaking of no nourishment, could successfully resist 

 yielding to frost in regions subject to a temperature of over 70" F. below zero, and when in 

 summer the soil only thaws to the depth of 12 or 15 inches, the ground below this depth 

 being perpetually frozen ? 



The meteorological tables of the English Arctic Expedition of 1875-6 show that 

 the mean temperature of the winter months at the stations of the two vessels. Alert and 

 Discovery, varied from 5" F. below zero in Octotier and 17" F. below zero in April to 

 40" F. below zero in the middle of the winter, and that the minimum temperatures 

 recorded were: — 73f " F. at the winter quarters of the first named v^essel, and — 70-8" F. 

 at the station of the latter in Discovery Bay. 



In spite of these terrible temperatures the naturalists attached to the expedition were 

 very successful, and Mr. Robert McLachlan, F.R.S., to whom the collections of insects 

 were submitted, wrote as follows in his report : 



" The materials brought home from between the parallels 78" and 83" N. latitude, 

 showed quite unexpected, and, in some respects, astonishing results, I have no hesitation 

 in saying that the most valuable of all the zoological collections are those belonging to 

 the entomological section, because these latter prove the existence of a comparatively 

 rich insect fauna, and even of several species of showy butterflies, in very high 

 latitudes." 



But the most interesting account of experiments on this subject which I have seen, 

 is that given by Commander James Ross, R.N., F.R.S., and inserted by Curtis in the 

 Entomological Appendix to the "Narrative" of Sir John Ross's second arctic voyage. The 



