THE MONTHLY BULLETIN. 



485 



The Adult. The adult female {F\y;. 114) is a small black wasp-like 

 iusect about 4.50 mm. in length. Head (excepting eyes) and thorax 

 punctate and sparsely covered with very short tine hair. Wings clear 

 and seem a trifle small in proportion to the body. Abdomen large, 

 shining black, last segment and ovipositor sheath covered with short 

 light colored hair. Adults observed, when disturbed did not seem to be 

 capable of tlying very far, but confined their efforts more to springing. 

 As far as observed the entire metamorphosis occurs inside the bud and 

 the adult gnaws its way to freedom. 



KiG. 114. — Adult of Isosoma orchi- 

 deariim. (Original.) 



Control. The eradication of this insect is a perplexing problem as 

 the orchid enjoys a warm damp atmosphere and forcing is resorted to. 

 which keeps the i)lant in a growing condition nearly the entire year. 

 This factor favors the development of the insect and consequently the 

 generations are continually overlapping. Control measures such as 

 injecting nicotocide into the infested bud. also piercing the larvie with a 

 triangular dissecting needle have been tried from time to time but with 

 apparently no great success. Tlie most practical control measures are 

 constant watchfulness, fumigation with a vaporizing insecticide for the 

 adults, and the cutting and burning of infested buds. This seems like 

 heroic treatment but if not taken in time this insect will quickly 

 destroy a prize collection of plants. 



Summary. In view of the wide distribution and destructiveness of 

 this insect, persons contemplating the importation of orchids should 

 insist on the most thorough of certifications and in.spections. 



