Observations on the morphology of adults and juveniles of Xiphinema americanum Cobb, 1913

Observations on the morphology of adults and juveniles or Xiphinema americanum are based on the study or a very large number of specimens collected from the campus of Aligarh Muslim University, AIigarh, during different periods of the year. Both sexes occur though males are extremely rare and their role in reproduction is doubtful. The four juvenile stages can easily be distinguished from each other as well as from the adults on the basis of their body length, size of functional and replacement odontoslyle, size of genital primordia etc.