59 



A NEW THKIPS DAMAGING ORCHIDS IN THE WEST INDIES. 



By 0. B. Williams, M.A., F.E.S. 



The thrips described below has recently been a source of considerable damage 

 to orchids grown for ornamental purposes in Trinidad, West Indies. Up to the 

 present it has not been found on wild orchids and it is possible that it is not 

 indigenous to this island. A large number of orchids are brought over from 

 Venezuela and it may have been imported with them from that country. 



Order THYSANOPTERA. 

 Family Thripidae. 

 Physothrips xanthius, sp. nov. 



$. Measurements. — Total length, about 0-9 mm. Head, length, 0-076 mm., width, 

 0*132 mm. ; prothorax, length, 0*088 mm., width, 0*160 mm. ; pterothorax, 



greatest length, 0*180 mm., width, 0*200 mm. ; abdomen, width, about 0*180 mm. ; 

 wing, length, 0*580 mm., width of middle, 0*028 mm. 



Antennae . . 1 2 3 4 5 



length (p) . . 22 31 34 48 40 

 width (fj) . . 29 24 18 17 15 

 Total length of antenna, 0*290 mm. 



6 



7 



8 



52 



9 



14 



13 



6 



4 



