350 ARACHNOIDEA. 



CASE the Phytopti might be the homologues of the missing legs, but 

 their position is not favourable to that view, and now the 

 discovery of the right number of warts and bristles on or near the 

 right place, gives greater probability to the view first taken by 

 Latreille, that the Phytopti form part of the section Sarcoptidae. 

 Nor can Dujardin's discernment be passed over without acknow- 

 ledgment. If his Phytopti belong to the Sarcoptidae, they are 

 not the less a very distinct and special section of that tribe. 



We must not, however, be too confident in the absolute cer- 

 tainty of the above conclusion. All that we can say is, that it 

 seems the most probable solution of the difficulty ; but we must 

 remember that the premises are but imperfectly established. 

 The warts and bristles have not yet been observed on all species, 

 nor in every individual. But, on the other hand, we must 

 remember that even although competent observers should fail 

 to find them, they may be sexual, and only present in one sex ; 

 or the bristle may be hyaline and not always distinguishable, a 

 thing which, under the most favoured circumstances, must always 

 be of extreme difficulty. Moreover, one positive observation by 

 a reliable witness should carry more weight than a hundred 

 negative ones. And lastly, when the insect is alive it is restless 

 and keeps swaying its head about, so that a confirmed long look 

 at any part of it is impossible. When it is dead the parts become 

 flaccid, and it is still worse, so that while there is plenty of apology 

 for not being able to make out all the parts, that very fact should 

 make us slow to form an opinion, and open to change it should 

 fresh argument or discovery give a new aspect to the case. 



There are other puzzling difficulties connected with these mites 

 and with the production of their galls. One of these is, whether 

 the same mite makes more than one kind of gall, or does more 

 than one kind of mischief. We think not ; but according to more 

 than one author who has searched for Phytopti, the same species 

 is found in different galls on different plants, and indifferently in 

 galls and in ungalled buds. Dujardin states that he found the 



