50 THE ENTOMOLOGIST. 



found the insect at rest in the daytime on the trunk of a tree ; a 

 small tree or sapling, he could not remember which, nor did he 

 know the name of the tree, but that did not much matter. What 

 chiefly impressed me about the creature was the great resem- 

 blance it had to an ordinary piece of bark, and how remarkably 

 well its colours seemed adapted in combination with every other 

 feature to bring about that resemblance. Not that there was 

 anything wonderful in all that ; resemblances of a similar kind, 

 many of them quite as perfect, some even more so, are quite 

 familiar to us ; and they are especially abundant amongst the 

 Phasmidae. But we know that the " stick " insects and " leaf " in- 

 sects do not go and hide themselves under water all day ; and I 

 had a vague recollection that that was what Prisopus was supposed 

 to do. It was impossible to believe this of the insect before me ; 

 for, in such case, its colours and all the remarkable adaptations of 

 structure I noticed could have no use and no signification. So 

 I determined to refresh my memory, and to find out what was 

 known about the habits of the genus. 



Turning, first of all, to the / Cambridge Natural History ' 

 where, as I knew, there was a most interesting account given 

 of the Phasmidse and their habits, I came upon the following 

 statement : — " In Brazil a species of the genus Prisopus has the 

 peculiar habit of seeking shelter under the stones submerged in 

 the mountain streams ; to enable it to do this it is remarkably 

 constructed, the under side of the body being hollowed, and 

 various parts set with a dense fringe of hairs ; the insect is 

 supposed to repel the air from the body in order to adhere to 

 the upper surface of a stone, where it sits with its fore legs 

 extended in front of its head, which is directed against the 

 current." 



That was a sufficiently startling statement about a species 

 of Phasmidae, and I felt certain that Dr. Sharp would not have 

 made it except upon very good authority. Who or what was 

 this authority I had now to find out. So I looked up the genus 

 Prisopus in the most recent work on the family, an excellent 

 monograph by Brunner von Wattenwyl and J. Kedtenbacher, and 

 very soon found what I wanted. The authors say of Prisopus 

 that: — ''This remarkable genus lives, according to Murray, in 

 water, where with their hollowed-out ventral side the insects 

 hold on to stones, with the body directed up stream." The 

 same story again, more briefly stated, for which Murray, it 

 appeared, was the authority. 



Andrew Murray was a well-known scientific man, and an 

 entomologist of wide experience, who had written much about 

 various groups of insects, including the PhasmidsB, to which he 

 had given a very fair amount of attention. What he had to say on 

 the subject, therefore, was bound to be of considerable interest. 

 It is to be found in his paper ** On the Habits of the Prisopi," 



