Caudal bursae of Heligmosomoides spp., from China, ventral views: 17, 18, H. p. polygyrus in Mus musculus, 17, from Shenyang, 18, from Changchun; 19, 20, H. neopolygyrus in Apodemus agrarius, 19, from Shenyang, 20, from Changsha; 21–23, Heligmosomoides incertae sedis, 21, in A. agrarius, from Antu, 22, in A. peninsulae, from Liang-Cheng, 23, in A. peninsulae, from Hulin. After Asakawa et al. (1993) and modified.

Scale bar: Figs 17–23: 100 μm. Letters in brackets referred to Fig. 1 of Asakawa et al. (1993). Grey bars show level of divergence of rays 4 and 5 and arising of rays 6 on the common trunk of rays 4 to 6: Figs 17, 19, 20, 23, in both lobes rays 6 arise proximally to the level of divergence of rays 4 and 5; Fig. 18, in left lobe ray 6 arising proximally to the level of divergence of rays 4 and 5, in right lobe at same level as the divergence of rays 4 and 5; Fig. 21, in both lobes rays 6 arising slightly distally to the level of divergence of rays 4 and 5; Fig. 22, in both lobes, rays 6 arise at same level as the divergence of rays 4 and 5.