NO. 6 CLASSIFICATIOX OF NEMATODES FILIPJEV 59 



cholaiminae, but the lips are more complicated. After 

 Southern, 1913. 



Fig. 13. Etirystomina assimilis (de Man), showing the mouth capsule 

 without lips ; the large onchium can be protruded outside 

 the capsule. After Filipjev, 1918. 

 Fig. 14. Eurystomina assimilis (de Man), showing the male tail. Note 

 the strongly curved, thin spicules and the two preanal 

 organs. After Filipjev, 1918. 

 Pl. 2, Fig. 15. Symplocostoma ponticum Filipjev, showing a mouth capsule 

 very similar to that of Eurystomina; in addition to the 

 chief onchium or spear, there is a little guiding onchium 

 on its side ; a part of the bottom of the mouth capsule has 

 become isolated, forming the cuticular "lens." After Filip- 

 jev, 1 91 8. 



Fig. 16. Enchelidium longicolle Filipjev, supposed to be the male of a 

 symplocostomoid female ; the mouth capsule is reduced ex- 

 cept for the "lenses". After Filipjev, 1918. 



Fig. 17. Trilobus brevisetosus (W. Schneider), showing the large 

 mouth capsule followed by a back chamber with two little 

 denticles inside ; there is no "circumoral pocket". After 

 Filipjev, 1929. 



Fig. 18. Tripyloides marinus (Biitschli). Note that the general shape 

 of the mouth capsule recalls that of Trilobus, but the mouth 

 can be opened wide as in Tripyla; the amphids are spiral. 

 After Filipjev, 1929. 



Fig. 19. Halanonchus macruriis Cobb. Note that this is similar to 

 other Tripyloidinae as regards its spicular apparatus, but 

 it has a pocketlike amphid. After Cobb, 1920. 



Fig. 20. Dorylaimtis regius de Man, showing its typical "dorylaimoid" 

 esophagus, narrow anteriorly and gradually widening poste- 

 riorly. After Steiner, 1927. 



Fig. 21. Tylencholaimus mirabilis (Biitschli), showing the head with 

 the three-lobed spear. After de Man, 1884. 



Fig. 22. Hygolaimus menseli Micoletzky, with the spear distinctly on 

 one side of the mouth capsule. After Micoletzky, 1925. 



Fig. 23. Dorylaimiis stagnalis Dujardin, with the typical spear guided 

 by the two vestibular rings. After Filipjev, 1929. 



Fig. 24. Dorylaimtis regius de Man, showing the tail of the male. 

 Note the wide spicules with a longitudinal chitinous ridge 

 in the middle, the preanal median row of papillae, and the 

 strong bursal musculature. After Steiner, 1927. 



Fig. 25. Mermis nigrescens Dujardin, showing the tail of the male. 

 Note that the strong bursal musculature and the preanal 

 row of papillae recall the Dorylaimidae. After Hagmeier, 



1913- 

 Fig. 26. Mermis tenuis Hagmeier, showing the head with the huge 

 pocketlike amphids. After Hagmeier, 1912. 



