118 



everything in the s\in, and then lay down ourselves. We could not see any 

 blow-flies about, of which there are so many in all parts of the country. 

 I soon fell asleep ; I think Mr. Whitcombe did the same, but he awoke first, 

 looked at his watch, and said we had been resting for an hour and a half, that 

 we must pack up, and get on our way. I quickly set to work to tie up my 

 swag, but the blow-flies had found us out, and had covered everything with 

 their eggs. His oj^ossum rug was the worst ; we cleaned everything as well as 

 we could, packed them up, and descended once more among the spray." 



The situation referred to in the above extract was some few miles beyond 

 the Rakaia saddle, on tlie western side, and in the very heart of the Southern 

 Alps, a locality remote from all human habitations, and pi'obably never before 

 visited by man. 



The circumstance above referred to indicates that the sense of smell in 

 these creatures, or at least " that power which communicates analogous 

 intimations to the sensorium," is highly developed, for it has been observed 

 that the distance from which they collect is often very great indeed. Whether 

 the peculiar club-shaped processes upon which the antennae are fixed are organs 

 of smell, is a point upon which I am not able to offer any positive opinion, 

 though, from the fact that many distinguished writers on insect structure have 

 assigned their olfactory perceptions to various ajjpendages of the head, and 

 from the apparent connection of the antennte with these perceptions, I am led 

 to conjectui^e that the organs in question have some important relation with 

 that sense. This is a point, however, which I must leave to be determined by 

 those who are better acquainted with insect anatomy and physiology. 



In connection with the numbers and very general distribution of the fly in 

 question, it has often been matter of wonder upon what it feeds, and how it 

 is propagated in many of the localities in which it abounds. For example, in 

 the recesses of the forests and upon the summits of alpine mountains the amount 

 of animal life of any kind, and consequently of decomposing animal mattei', is 

 extremely small, and if we except decaying vegetable matter in the forests, 

 there is nothing to be seen which is even apparently capable of aflfording food 

 to its larvae. I may state, too, that although I often cearched most diligently, 

 I never found any of the larvae in such situations. So completely are these 

 points involved in mystery to me, that I am unable even to hazard a conjecture 

 on the subject. In England, the annoyance sufiered by sheep from the attacks 

 of the flesh-fly is matter of notoriety, and I believe it has been asserted, 

 that unless constant attention were paid to these animals when labou.ring under 

 diarrhcea, or when suffering from wounds, they would soon be devoured by its 

 insatiable larvae. 



Now, it is somewhat marvellous, and certainly providential, that none of 

 the Flesh-flies of these Islands (of which there are several species) are known to 

 annoy the living sheep, except when " cast," that is, when lying upon its back 



