NO. 2131. 



NEMATODE PARASITEf^ OF RODENTS— HALL. 



197 



Fig. 251.— Gongy- 

 lonejia beevi- 



SPICULUM. AN- 

 TERIOK EXTREM- 

 ITY. Enlarged. 

 After Seurat, 

 19M. 



GONGYLONEMA BREVISPICULUM Seurat, 19146. 



Specific diagnosis. — Gongylonema (p. 191) : The mouth is situated 

 in the center of a disk which projects slightly (fig. 251) ; the buccal 

 cavity is shallow. The cuticle is finely striated at 

 intervals of 10 ix. There are 1 rows of bosses on the 

 dorsal and 1 on the ventral surface. There are 2 lat- 

 eral alae, originating about 210 p. from the anterior 

 end of the body and not extending beyond the region 

 of the bosses. Immediately anterior of these alae are 

 the 2 precervical (cervical) papillae. The excretory 

 pore opens on the ventral surface in the posterior 

 third of the interval from the nerve ring to the in- 

 ferior limit of the muscular esophagus. There is an 



unpaired dorsal papilla 2 

 mui. posterior of the teruii- 

 nation of the esophagus. 

 The nerve ring is located 

 at two-fifths of the distance 

 from the anterioi- to the posterior end of 

 the esophagus. 



Male 17 mui. long with a maxiuuun 

 thickness of ll'O ix. Lateral alae originate 

 175 IX from the anterior end of the body. 

 Buccal cavity 35 /x long (?). Muscular 

 esophagus 530 ^ long; "total length of 

 esophagus one-fourth of entire body length. 

 The short tail is not straight but is slightly 

 bent to the left (fig. 255). The cloacal 

 aperture is 180 ix from the posterior end of 

 the body. The caudal alae are well devel- 

 oped and slightly unequal; the left one is 

 the longer, 180 /a long ; the right one is 420 

 IX long. There are 6 pairs of preanal pa- 

 pillae, all stalked, and 1 pairs of stalked 

 and 2 of sessile postanal papillae, the latter 

 very small and located near the tip of the 

 tail close to the apertures of the caudal 

 glands. The spicules are very une({ual ; 

 the filifoi-m left spicule is GGO //, long, 

 and the short thick right s]:)icule is 85 /x 

 long and 18 /x thick. The gorgeret 

 (gubernacuUnu) is asymmetrical, being 

 prolonged posteriorly on the left side to form an elongated 

 branch. 



Fig. 255.— CrONGYLONEMA BREVI- 

 SPICULUM. a, Posterior ex- 

 tremity OP MALE, VENTRAL 

 view; 6, right .spicule and gu- 

 bernaculum, dor.sal view. 

 After Seurat, 1914. 



