126 JOURNAL OF ENTOMOLOGY AND ZOOLOGY 



dry, and during the summer is hot. The species has been present 

 here for at least fourteen years, and has consequently had much 

 time in which to be disseminated. For these reasons we should 

 expect to find the mite quite generally distributed over this 

 section. 



Weldon ('09) gives several records of a species of red spider, 

 which he called T. bimaculatus Harvey, in western Colorado. 

 Here this species has been reported as doing very serious injury 

 to orchards. I have received several specimens of these mites 

 supposed to be the common spider mite, but found that they 

 were of a new species. This species was described as T. weldoni 

 Ewing. Yet notwithstanding this fact, since reading again 

 Weldon 's bulletin, I am of the opinion that the common red 

 spider was present also, and generally distributed in western 

 Colorado. 



Notes on Questionable Eecords 



The questionable records given in the tabular data concerning 

 the distribution of this species in the United States, and repre- 

 sented by a circle with cross in the map, are of four kinds. 



a. Records which probably refer to Tetranychus weldoni 

 Ewing. 



b. Records which probably refer to Tetranychus flavus 

 Ewing. 



c. Those where no specific determinations were made, but 

 which probably refer to Tetranychus telarius Linn. 



d. Memory records. 



The questionable records given for western Colorado probably 

 refer to Tetranychus weldoni Ewing. These were reported under 

 the name of Tetranychus bimaculatus Harvey. 



The questionable record from North Dakota refers to a species 

 of spider mite that caused serious damage to spruce trees in 

 1912, according to Professor C. B. Waldron, of the North Dakota 

 Agricultural College. In this instance no specific determination 

 was made. 



The record for Oklahoma refers to a species of red spider that 

 was doing serious damage to a field of wheat at Wheatland, 

 near Oklahoma City ; no specific determination was made. 



