SPINNING MITES. loi 



CASE than that of the camellia : it carpets the under side of the leaves 

 vni. . . . . 



of the Dracaena with threads of silk, on which it walks like a 



spider. It does a great deal of harm to the leaves that it sucks, 

 stopping their vegetation and causing them to become diseased. 

 It is not difficult to destroy them ; to do so it is sufficient to place 

 the plants attacked by this vermin in a cold house during two or 

 three days. M. Savage brought us a Dracaena australis on which 

 these parasites could be counted by hundreds. It had scarcely 

 remained twenty-four hours in our cabinet, when all had disap- 

 peared ; the change of temperature had completely killed them." 

 The only specific character here given is the colour, which, as we 

 have already said, varies much in the red spider. 



The following for the same reasons does not appear any better 

 entitled to rank as a separate species. 



TeTHANYCHUS TELARIUS Vat.; H/EMATODES {Boisd.), Ent. Hort., p. ^"S. 



M. Boisduval says that this little parasite was observed by 

 M. Riviere on the leaves of the red variety of the Ricinus 

 (Ricinus communis), frequently cultivated now-a-days in the 

 squares and gardens of Paris. 



It is rounded oval, of a deep blood red ; it spins under the 

 leaves, between the divisions of the first nervures, a slack tissue 

 like little spiders' webs. It is very small, and only visible with a 

 strong magnifying glass. M. Boisduval suggests that his haema- 

 todes approaches a good deal to the Raphignathus ruberrimus, 

 which Duges discovered under stones, and which he described as a 

 new species ; but there is nothing in his description that supports 

 this except the colour, and that may depend on the food-plant. 



Tetranychus TELARIUS Va7'.; TiNi {Boisd.), Ent. Hort., p. 91. 



The laurustinus, which grows naturally in the south of France, 

 and those which are cultivated in the gardens of Paris, are 

 subject to a kind of grise, as it is called, occasioned by a little red- 

 dish mite, which multiphes in a prodigious way on the under side 



