The structures and morphometric comparisons of the pre-parasitic juveniles of the following Mermithidae (Nematoda) were studied. Romanomermis wuch-angensis, Hexamermis albicans, Hexamermis agrotis, Hexamermis feng-chengensis, Hexamermis sp., and Amphimermis sp. Duncan's new mutiplt-rangt test (P = 0.05) was used to analyze the morphometric data of the juveniles. The results showed that there were some distinguished morphological differences among genera and that morphometric comparisons among species in the same genus differed significantly. The possibility of pre-parasitic juveniles be used f...
