PARASITIC ROUNDWORMS -27 



36 (35) No trifid cervical papilla present. 



Acuaria ardcac (A. J. Smith) i.^o^. 



Male unknown. Female 17 by 0.7 mm. Two lateral lips, each with double papillae From 

 base of each lip two promment submedian ridges on surface extend posteriad nearly to ccntt-r lA 

 body, then dorsad and ventrad respectively to join similar lines on opixjsiic side. Ksi.phaifu* 

 2 mm. long, in two sections: anterior narrow region o.S by 0.05 to o.oy mm., ixjstrrior widrr 

 region 1.2 by 0.2 mm. Anus 0.35 from tip of tail which is bent strongly dorsjid. Vulva nt-.ir 

 center of body; no eggs developed. 



In Ardea herodias. Described originally as Dispharagiis ardeae by A. J. Smith. 



37 (30) Preanal papillae in male numerous, grouped in pairs and stalked. 



Family Thelaziidae Raillict 1916. 



Head naked or provided with cuticular thickenings or helmet-like covering. Mouth with 

 2 to 6 very small lips or without any, followed by a long vestil)ule or a short butial capsule. 

 Esophagus composed of two distinct regions. Males with or without lateral alac in caudal 

 region, with a linear row of numerous preanal papillae, often paired; postanal i)apillae lc*« 

 numerous; 2 spicules, almost always unequal. Female with double uterus; vulva variable 

 in location. Oviparous or viviparous. 



Only genus in North American aquatic hosts. 



Cystldicola Fischer 1797 . . 38 

 No valid record exists for the European C. Jarionis in North .\merica. 



38 (39) In air-bladder of salmonid fishes. 



Cystldicola stigmatiira (Leidy) 1886. 



Length: male, 12 to 25 mm.; female, 20 to 40 mm. Width: male, 0.25 mm.; female, 0.4s 

 mm. Mouth circular with 2 minute lateral teeth. Buccal capsule tubular, 0.12 to 0.2.J mm. 

 long. - Anterior region of pharynx 0.5 to 0.6 mm. by 0.054 Tnm., posterior region 2.1 to 2.\ 



mm. by o.i mm. Male with 



narrow lateral membranes on 



caudal end ; 5 pairs of single 



postanal papillae, 9 pairs of 



double preanal papillae. Two 



unlike spicules; one slender oS 



to 0.9 mm. long, o.oi mm. wide; 



other trowel-shapeti, 0.16 mm. 



Fig. 820. Cystldicola stigmatura. Anterior end of female. X 85. \q^^ q jg ^im wide Female 



(After Ward and Alagath.) s^^^;^, ^^^e near center of Ixxly ; 



uterus with anterior and posterior branches both well developed and symmetrical. Ova thin 



shelled, containing developed embryo when laid, 44 by 27 /x. 



In air-bladder of Great Lakes trout, white fish, and lake herring. Lake Eric, Lake St. 

 Clair, Lake Michigan, Lake Ontario (Leidy). 



In half or more of fish examined. Reported by Wright as Ancyracanthus cystidkola and by 

 Leidy as Filaria stigmatura. 



39 (38) In heart of white fish Cystldicola scrrata (Wright) 1S79. 



Length 11 mm. With several small teeth around anterior end instead of two as in former 

 species. Only a single specimen found by Ramsay Wright at Toronto. I'erhaps an imma- 

 ture specimen, either migrating in blood stream, or accidentally introduced into this peculiar 

 location. 



40 (29) Male with conspicuous ventral ridges near posterior end; preanal 



papillae absent or inconspictious. Body spinous. 



Splnltcctiis Fourment 1S83. 



Mouth without lips or papillae. Except at extreme tip the body is encircli«d in the ante- 

 rior half or more by rows of spines pointing backward. The ventral surface in the male carnes 

 several parallel series of rugosities just anterior to the anus. 



Representative North American species. 



Splnltcctiis gracilis Ward and ALigalh. 



Mature female 17 to 19 mm. long, 0.14 broad; male 12 mm long, 0.075 mm broad. ^}^^f 

 130 rows of spines with 40 to 50 in each row. .Interior tip free from spmes for o.n mm. in 



