308 ANNUAL OF SCIENTIFIC DISCOVERY, 



the vibratory motion the bird gives them ; while the two immensely 

 long filaments of the tail hang in graceful curves below. 



The natives procure the Bird of Paradise by building a small in- 

 artificial-looking hut in the tree while the birds are absent, and shoot- 

 in- them with arrows when a sufficient number have arrived, by 

 concealing themselves in the hut. 



" Nature," says Mr. Wallace, "seems to have taken every precau- 

 tion that these, her choicest treasures, may not lose value by being 

 too easily obtained. First we find an open, harborless, inhospitable 

 coast, exposed to the full swell of the Pacific Ocean ; next a rugged 

 and mountainous country, covered with dense forests, offering, in its 

 swamps, precipices, and serrated ridges, an almost impassable barrier 

 to the central regions ; and, lastly, a race of the most savage and 

 ruthless character in the very lowest stage of civilization. In such a 

 country and among such a people are found these wonderful produc- 

 tions of nature. In those trackless wilds do they display that exquisite 

 beauty and that marvellous development of plumage, calculated to 

 excite admiration and astonishment among the most civilized and 

 most intellectual races of man." 



POISONS NOT ALWAYS POISONS. 



Mr. J. Attfield lately read a paper before the London Pharmaceuti- 

 cal Society, in which he stated that he had discovered that some of 

 the most active extracts in the pharmacopoeia extract of colocynth 

 and extract of nux vomica, for example supported colonies of 

 lively little animals, greatly resembling cheese-mites. They proved, 

 in fact, to be a hitherto unknown species of acari. Other irritating 

 substances have been known to support similar animals. Ginger has 

 been found to be infested with them ; but in this and similar cases it 

 was supposed that they lived on the starchy matter, and rejected the 

 active principle. But it was impossible that they could eat ex- 

 tract of nux vomica without eating strychnia. It might be, however, 

 that the strychnia was not assimilated. Mr. Attfield, therefore, col- 

 lected some acarine excrement (the excrement floats on, while ex- 

 tract of nux vomica sinks in water), tested it for strychnia, and only 

 discovered a trace of that body, which he believed to have been dis- 

 solved off from the extract by the moist excrement. But, to prove that 

 these animals could live on food that was to other animals a deadly 

 poison, Mr. Attfield took several of them from the extract and put 

 some into microscopic cells containing powdered strychnia, and others 

 into empty cells. In two days those in the empty cells were starved 

 to death, while those supplied with strychnia were as lively as ever. 

 Some of the animals from extract of colocynth lived just as well on 

 strychnia, and, indeed, seemed equally well, whether their food was 

 colocynth, strychnia, morphia, or cheese. As "poison-mites" rel- 

 ished cheese, Mr. Attfield thought cheese-mites might relish poison. 

 He therefore took some from cheese and put them on powdered 

 strychnia, but the experiment was fatal to them; they all died. 

 Others, however, thrived on cheese, adulterated with twenty per 

 cent, of strychnia. Mr. Attfield infers that acari digest strychnia, 

 which becomes oxidized in their blood, and its chiet elements re- 



