10 



PARASITKS <>I THE (OTToX BOLL WEEVIL. 



Fig. l. 



-Bracon mellitor, parasite of boll weevil. Much 

 enlarged (from Hunter and Hinds). 



HISTORY. 



Prior to the year L906 very little information concerning the para- 

 sites of the boll weevil had been accumulated. In 1895 Townsend 



mentioned a small hymen- 

 opterous parasite; also re- 

 corded the suspicious oc- 

 currence of several species 

 of Scymnus in the squares, 

 and mentioned that a fun- 

 goid parasite, a species of 

 Cordyceps, "was found 

 growing out of a dead pupa 

 in its cell in a boll, Novem- 

 ber 26, in a field in San 

 Juan Allende, Mexico." 

 (Townsend, 1895.) a In 

 1896 Doctor Howard 

 stated that the parasites 

 were only abundant late 

 in the fall and that from 

 '15 to 20 per cent of the 



w T eevil larvae in fallen squares in November at Beeville and Kenedy 



were destroyed by parasites." 



(Howard, 1897.) 



In 1901 Professor Herrera 



published a preliminary note 



concerning Pediculoides ven- 



tricosus Newp. (fig. 2) (R an- 

 gel, 1901b, p. 206), and in the 



same year a more extensive 



note on the work of this mite 



was published by R angel. In 



testing the mite's ability to 



propagate, 250 squares were 



divided into lots of 50 each 



.'ind an infested larva placed 



with each lot for four days. 



One hundred check squares 



were used. At the time of 



examination the check squares 



w T ere free from the mites, while 



the others contained 193 wee- 

 vil stages, of which 61 were 



attacked by Pediculoides; in other words, 31.6 per cent were parasit- 



Fig. 'l.^Pcdiculoidrs ventricosus, mite enemy of boll 

 weevil. Much enlarged (adapted from Brucker). 



" Bibliography, pp. 50-51. 



