Julida ring VII sections. (A-E) N. kochii male, para-midsagittal (A-C) and frontal (D-E) paraffin sections of rings VI-VIII during post-embryonic stadia IV-VI. Mallory's triple stain. A, last stadium with walking legs on ring VII. B, stadium with gonopod primordia. C-E, adults with gonopods. (F-G) N. varicorne male, frontal paraffin sections of rings VI-VIII during post-embryonic stadium V. Mallory's triple stain. Labels a-d in panel C mark the levels of sections in Figure 9. agA, anterior gonopod apodeme; aga, anterior gonopod abductor muscle; agr, anterior gonopod retractor muscle; gt, gut; nc, nerve cord; pgr, posterior gonopod retractor muscle; ph, prophragma; arrows, possibly undifferentiated tissue. Asterisks, ring VII legs. Anterior to the left, scale bars 100 μm.