ENGLISH SPECIES OF RED SPIDER. 55 



Colour. Body pale yellowish green ; sometimes minute dark 

 specks, arranged in four small clusters, are present at the sides 

 and posterior end of the dorsum. 



Measurements. 6 , length 220-250 ^ ; $ , 340-380 fx. 



Host plant. South American tree {Talisia j^rinceps), growing in 

 Tropical Greenhouse, Kew Gardens. 



5. Tetranychus telarius L. 



Acarus telarius (ad part.) Linnaeus, Syst. Nat. 1758, Ed. 10, 

 p. 616. 



Tetranychus telarius 0. L. Koch, Deutsch. Crust., Myr., Arachn. 

 1838, heft 17, no. 12. 



T. russeolus C. L. Koch, op. cit. heft 17, no. 15. 



T. urticce 0. L. Koch, op. cit. 1835, heft 1, no. 10. 



Acarus telarius Boisduval, Ent. Hort. 1867, pp. 82-84, text- 

 fig. 4. 



A. cucumeris Boisduval, op. cit. p. 84. 



A. vitis Boisduval, op. cit. pp. 92-93. 



Tetranychus althcece Yon Hanstein, Zeitschr. wiss. Zool. 1901, 

 Ixx. p. 74. 



T. telarius Ewing, Ann. Soc. Ent. America, 1913, vi. pp. 455- 

 457, text- fig. 1. 



2\ althcece Tragardh, Stockholm Medd. Oentralanst. Forsoksv. 

 Jordbruksomr. 1915, vol. 109, pp. 36-40 & 57. 



c5" . Penis strongly curved near the end, and the tip furnished 

 with two minute but distinct barbs. 



Palp. Terminal finger of moderate length (about as long as the 

 two rod-like setaj situated near it). Dorsal sensory finger varying 

 slightlj'-, but visually short and slender (sometimes, however, it is 

 somewhat club-shaped). 



Claio of first leg in this sex with a little dorsal offshoot, the 

 rest of the claw being divided into six short slender forks or teeth 

 (three on each side). 



5 . Palp. Terminal finger fairly well developed, but not very 

 long. Dorsal sensory finger also fairly well developed. 



Colour usually pale, being either whitish, greenish, or yellowish 

 in tint, with dark lateral spots or patches varying in extent, 

 sometimes quite extensive. More rarely pink or reddish indi- 

 viduals are met with. 



This species occurs on many plants, and was confused by 

 Linnteus, and later by Hermann, with the form occui-ring on the 

 lime-tree (the latter creates the name tiliarium, but says that the 

 species occurring on the lime-tree is also found on Althaea, 

 a typical plant host for T. telarius proper). This mistake is 

 followed by many other authors, including recent authors of great 

 repute, and several other quite distinct species — viz., T. lintearitis 

 Dufour (from gorse), T. populi 0. L. Koch (from poplar trees), 

 and the species living on the oak (Oligonychus quercinus) — have 

 also wrongly been regarded as synonyms of T. telarius. 



