THE ACAPJXA UK MITKS. 



87 



as a dry powder or lime-sulphur used as a spray. McGregor advocates the use of 

 potassium sulphid, 3 pounds to 100 gallons of water. Bisulphid of lime is also an 

 effective remedy, and tobacco water is sometimes used. 



Tragardh has recently revised the Swedish Tetranychus, and di\'ided the genus: 

 Tetranychus is retained for species with the claw divided into foiu* parts; Paratetrany- 



FlG. 48.—Achelcs. 

 (Original.) 



49.— TetranycTioides californica, and palpus enlarged. 

 (Author's illustration.) 



chus for those with claw entire, and Schizotetranychus for those with claw in two parts; 

 the latter genus includes T. mytilaspidis and T. pratensis; while T. modestus, T. sim- 

 plex, and T. yothersi go in Paratetr any chus. 



The species of Stigmaeus are elongate and have short legs. They are smaller than 

 Tetranychus but live in the same manner. Our one species, aS. floridanus Banke 



Fig. 50.- 



-Eaphignathu^ brevis. 

 (Original.) 



Fig. 51. 



TetTanychopsi 

 (Original.) 



sptnosa. 



(fig. 47), occurs upon the bases of the imbricated leaves of the pineapple. It is of con- 

 siderable economic importance, owing to the fact that its punctures give certain 

 destructive fungi access to the tissue of the leaf. The remedy, Prof. Rolfs found, is to 

 place a small quantity of tobacco dust in the bud of the plant, the dew and rain wash- 



