'2-24: The Feci Tlwip.s (Kakutlirips robustus) 



the eggs which he found embedded in the tissue of the stamen 

 sheath. He also beheved that the insect hibernated in the adult stage. 

 He suggests as a remedy 'topping' the plants as is done in beans for 

 'black-fiy,' as he found that the topmost shoots were most badly 

 attacked. 



In 19131 myself gave a preliminary account of the life-history, show- 

 ing that it is single brooded and passes the winter as a full fed larva in 

 the soil beneath the infested plants. 



In 1914 Vuillet (ii) described a Chalcid Thripoctenus brui n. sp. 

 which he found among larvae and adults of the pea thrips in France 

 and which he believes to be parasitic on it. 



Recently [Williams, 1914] I have separated the species robustus 

 from the genus FranMiniella and have erected for it a new genus KaJco- 

 tJirips on characters which will be given later. There are several 

 shorter or less important references which will be discussed as occasion 

 arises. 



Species and Synonomy. 



Although several different species of thrips may at times be found 

 in peas and beans, there is one in particular w^liich seems always to be 

 present in large numbers when any severe damage is recorded. This 

 is at present known to systematists as Kalolhrips robusfa. It belongs 

 to the family Thripidae of the sub-order Terehranlia of the Thysanoptera. 



To the unaided eye it appears as a minute black insect about a 

 twelfth of an inch (2 mm.) long, Hnear, more or less pointed at each 

 end, with short slender antennae. There is a lighter band across the 

 thorax due to the bases of the wings being pale coloured. The lighter 

 rings on the abdomen described by several authors are merely the 

 soft and lighter coloured connecting membrane between the abdominal 

 segments which shows when the body is distended, usually by killing 

 in alcohol. 



As the literature on the Thysanoptera is very scattered and often 

 difficult to obtain, the following notes on the characters of the family 

 and sub-order arie given : — the sub-order Terebraniia is chiefly char- 

 acterised, and may be easily recognised, by having the terminal segments 

 of the abdomen more or less constricted to a point (in the Tubulifera 

 the tenth segment is tubular), by having a saw-like ovipositor in the 

 female and two longitudinal veins more or less distinct in the front 

 wing. Th(! family Thripidae has the antennae six to eight segnuMited 

 and the ovipositor of the female curved downwai'ds. 



