FREE-LIVING NEMATODES 



489 



26 (27) Lateral dots much accentuated Spilophora Bastian. 



The striae are resolvable into rows of dots 



which are much accentuated on the lateral fields. 

 Genus of a score or more known species, 

 aquatic, mostly marine. 



Representative species. 



Spilophora canadensis Cobb 1914. 



&. 



; 15. 



■ ^ : 4.V- 



88.4 



■"SY.i ■ 



Lateral wings {3) are very prominent, and pos- 

 teriorly are somewhat scalariform. The females 

 have symmetrically reflexed ovaries. 



Habitat: Fresh-water ponds. Cape Breton Is- 

 land, Dominion of Canada. 



Fig. 786. Spilophora canadensis. 



a, mouth opening; b, dorsal tooth; c, pharynx; d^ 

 base of the pharynx; e, esophagus; /, nerve cells; g, 

 nerve-ring; h, excretory pore; i, valvular apparatus 

 of the bulb; j, longitudinal row of cuticular markings 

 characteristic of the genus; A, intestine; /, renette cell; 

 m, nucleus of renette cell; «, cell accessory to the 

 renette cell; 0, blind end of testicle; p, reversal of the 

 striationsof thecuticula; 0, vas deferens; f.spiculum; s, 

 anus; /, caudal gland; u, spinneret. (After Cobb.J 



27 (26) Striae composed of dots; the lateral ones little if any accentuated. 28 



28 (29) Pharynx without esophageal bulb Cyatholaimus Bastian. 



Pharynx is cup shaped then conoid, and 

 longitudinally ribbed. 



Genus of a score or more of aquatic 

 species, nearly all marine but found also 

 in brackish and fresh waters. Cyatho- 

 laimi are found in all tropical and tem- 

 perate seas, and the individuals are nu- 

 merous. In most habitats both sexes 

 will be found. Diatoms are sometimes 

 found in the intestine. Though not 

 shown in the species here figured, the re- 

 nette seems always present, and is often 

 well developed. 



Representative species. 

 Cyatholaimus truncatus Cobb 1914. 





"19 -I. 



2 3 r\2 6 



Habitat: Silver Springs, Fla. 



Fig. 787. Cyatholaimus truncatus. 



I, side view of a female; II, side view of 

 head; III, front view of the same head; 

 IV, ventral view of anal region of male; 

 y, lateral view of the same; VI, lateral view 

 in the middle of the body showing cuticular 

 markings and pores. 



o, submedian cephalic seta ; b, labial 

 papilla; c, amphid; i, dorsal tooth; e, lat- 

 eral cephalic seta; /, one of the twelve ribs 

 of the vestibule; g, small submedian pharyn- 

 geal tooth; h, base of the pharynx; i, ejac- 

 ulatory duct; j, intestine; k, one of the 

 four male pre-anal supplementary organs; 

 I, one of the spicula; m, anal muscles; «, one 

 of the accessory pieces; 0, nerve-ring; p, 

 one of the cells of the intestine; g, lumen of 

 the intestine; r, anus; s, blind end of re- 

 flexed ovary; t, egg; «, vulva; d, flexure 

 in anterior ovary; w^ junction erf the ovary 

 and uterus; x, pores m the cuticula; y, one 

 of the three caudal glands; 2, male glaad (?). 

 (After Cobb.) 



