25S ARACHNOIDEA. 



CASE plants that the mite has been observed chiefly on these bulbs. 

 We have observed in numbers, on the roots of vines attacked 

 by Phylloxera, a species which we cannot distinguish from T. 

 echinopus ; and it seems not unlikely that it may hereafter be 

 found on roots generally. We found Hypopi in its company on 

 vine roots. 



Rhizoglyprus phylloxek^ (Tyroglyphus phylloxera, PlaiicJion and Riley, 

 6th Report, 1874, p. 52). 



Mr. Planchon in his work on the Ameri- 

 can vine, and Mr. Riley (loc. cit), records 

 the presence of this allied species in North 

 America. They found it in association 

 with the Phylloxera of the vine, feeding in 

 its young state on the juices of the roots 

 injured by Phylloxera ; and, when older, 

 preying extensively on the root-inhabiting 

 type of that insect. Mr. Riley mentions 



Rhizoglyphus phylloxera. - - ,.- ,,.,_. 



Copied from Riie/s figure. that wheu this lact was published, it was 

 hoped that the introduction of the Rhi- 

 zoglyphus into Europe might be of service in reducing the 

 numbers of Phylloxera, and he received orders from vine growers 

 in France for a supply of the cannibal. Mr. Riley, however, 

 although he endeavoured to comply with the request, did not 

 anticipate that it would do much good ; — in which we agree with 

 him, chiefly because they have already in France commonly asso- 

 ciated with the Phylloxera a Rhizoglyphus, which we believe to be 

 the preceedmg species ; and the one should certainly be as good 

 as the other as an exterminator, if that class of mites really did 

 feed upon other insects ; but the statement of Messrs. Planchon 

 and Riley to that effect has been received with doubt by some 

 French entomologists. We have not seen M. Planchon's statement, 

 and we observe that Mr. Riley does not say how he ascertained 

 the fact ; but he makes the assertion broadly, and as he is well- 



