AGRICULTURAL EXPERIMENT STATION. 133 



The Two-Spotted Mite. 



{Tetranychns 2-maculatus, n. sp.) 



Ord. Acarina : Fam. Tetranychidse. 



We first noticed this species in Orono, Me., early in the spring 

 of 1891, upon rose bushes exposed in a window at the Post Office. 

 Since then it has spread to most of the plants in the window 

 excepting geraniums, for which it seems to have an aversion. Mr. 

 White whose rose bushes were infected thought the mites got on 

 while his plant was loaned to a sick lady, but on inquiring we 

 found no other plants were in the sick room at the time and the 

 only possible source of infection was cut plants, which was 

 improbable. In order to learn how general the distribution of 

 this mite was in this region, we visited several houses in Orono, 

 where house plants are kept, aud in the majority of places found 

 the mites doing considerable damage. Rejecting the positive 

 statement of one party that these mites are the same as lice on 

 hens and that her plants were all right until she set them out of 

 doors and some lousy fowls infested them, we are inclined to think 

 that the pest was introduced in Maine upon rose bushes and other 

 plants purchased of a prominent dealer. The parties whose 

 plants are infested in most cases had plants from this house and 

 one party positively affirmed that the roses received were noticed 

 to be infested when unpacked. Though great vigilance ought to 

 be exercised by dealers that the plants they send out are in 

 good health and not infested with injurious insects and fungi, yet 

 they cannot always be held responsible, especially when the 

 parasite is small and readily overlooked. Those who receive 

 infested plants will have to discard them, or fight the pest by aid 

 of known remedies. 



Even experience has been no protection against the introduction 

 of this mite for it has found its way into the large green houses 

 of the country, also in the green house at the college in our 

 own State and has been a source of much annoyance. 



The mite is so small it is next to impossible to examine green- 

 house stock or house plants carefully enough to prevent its intro- 

 duction, and the custom of exchanging slips of plants for 

 culture, so common in every neighborhood, aids greatly in its 

 rapid dissemination. 



The mite being firmly established in Orono and no doubt in many 

 other places in the State, and having given so much trouble at 



