1913] Taxonomic Characters in Tetranychus. 457 



Tetranychiis sexmaculatus Riley may be the same as T. 

 telarius Linn. I have received many specimens of this species, 

 sent by Professor H. J. Quayle, from Southern CaHfornia. I 

 find that the females agree with the females of T. telarius Linn, 

 in every minute detail of structure. I have transferred live 

 individuals to the common host plants of T. telarius Linn. 

 Here they have not thrived successfully. In most cases they 

 would not establish themselves. Unfortunately I have never 

 examined a male of T. sexmaculatus Riley, and since so much 

 depends upon the characters of the male genital armature we 

 cannot be sure of the synonymy of the two species until a male 

 specimen is examined. 



Tetranychus gloveri Banks appears to be the same as T. 

 telarius Linn. I have received scores of individuals of T. gloveri 

 Banks, on cotton, from Georgia, sent by E. L. Worsham. These 

 agree in all respects with my specimens of T. telarius Linn, 

 collected frgm many places in the United States, and with the 

 specimens of T. telarius Linn, received from Europe. Profes- 

 sor A. Berlese has examined specimens of T. gloveri Banks from 

 cotton, and has considered it as being the same as T. telarius 

 Linn. 



Tetranychus weldoni n. sp. ' 



I have received many specimens of red spiders from G. P. 

 Weldon labeled T. bimaculatus Harvey. For a long time I have 

 considered that they were this species, which is, as I have shown, 

 a synonym of T. telarius Linn. Recently I have found that the 

 male is different from the male of the T. telarius Linn. 



Female : Similar in all respects to the female of T. telarius Linn. 



Male: Different from male of T. telarius L. in characters of penis 

 and spur on palpus. Spur on palpus not so pointed as in T. telarius 

 Linn. Penis very long, rod-like; equal to a third the length of the body. 

 Inner lobe short, rod-like, slightly swollen at its anterior end. Shaft, 

 rod-like, not setiform; gradually tapering as you pass backward; 

 posterior one half turned upward; tip narrowly rounded, not pointed. 

 Basilar lobe absent. Hook absent. Barb absent. 



From Grand Junction, Colorado; on apple, prune, and cotton 

 wood; by G. P. Weldon. 



Tetranychus borealis n. sp. 



Female: Similar to the female of T. telarius Linn, but smaller, and 

 never orange or red. The inner prongs of the tarsal claw are stouter 

 than the inner prongs of the tarsal claw of T. telarius Linn. 



