This sounds all right—I mean the account of the apparatus—but according to Dr. Powell, of New Zealand, it is all wrong. Writing in the _Transactions of the New Zealand Institute_,[28] Dr. Powell, after quoting the above passage, says, “I am, of course, ignorant of the details of his description; but unless the cicada which he describes differs essentially in the nature of its musical organs from those found in New Zealand, and also from those described more or less correctly by other authors, especially Réaumur, he is most certainly in error.” Dr. Powell, then, after telling us that the stridulating organs of the cicada are constructed on a principle unique in nature, viz. a vibrating membrane, continues: “In the male, on the upper surface of the first ring of the abdomen, on either side, may be seen a crescent-shaped opening, and on examining this opening with a magnifying-glass it will be seen to lead into a shallow cavity, closed in by a horny membrane. This membrane is highly elastic, and the sound is produced by the contraction of the muscle straightening out the folds of the membrane; this produces a click and, on the muscle relaxing, the membrane, from its elasticity, springs back with another click.” That this is really the way in which the sounds are produced seems proved by the fact that “if a live insect be caught, and these membranes be observed during the act of stridulation, they will be seen to be vibrating rapidly in time with the beats of the shrill sound.” But what about the “wonderfully complex resounding apparatus, consisting of two cavities covered with scales”? After a full examination and various experiments, Dr. Powell arrives at the unexpected conclusion that the sound is in no way dependent upon these “large transparent, drum-like membranes,” as he calls the cavities in question. I was “much surprised,” he says, “to find that the large drums seemed to take no part in the production of the sound, and the idea occurred to me that they might be hearing organs; but on examining the females, which are dumb and do not possess the stridulating organs, I found that the drums exist, indeed, but are quite rudimentary instead of being large, as we should expect to find them, were they subservient to the sense of hearing.” If, however, the drums did answer the purpose of a resounding apparatus in the male, we should expect to find them exactly as they are in the female, and so strong does the evidence of their suppression in her appear to me, that I cannot help thinking that, in spite of all Dr. Powell’s observations and experiments, he was somehow mistaken, and that in nature they do act in this way.