NO. 2131. 



NEMATODE PARASITES OF RODENTS— HALL. 



41 



reasonable, though the writer is of the opinion that these and other 

 ascarids from rodents probably belong in some related genus rather 

 than in the restricted genus Ascaris. 



ASCARIS LAEVIS Leidy, 1856. 



Synonym. — Ascaris leuis Leidy, 190-i. 



Specific diagnosis. — Ascaris (p, 40) : 



Male unknown. 



Female 9 cm. long by 2r mm. thick. Lips prominent. Tail conical, 

 mucronate. 



Host. — Marmota monax (Arctomys monax). 



Location. — Intestine. 



Locality. — Not stated. 



The above description from Leidy is rather inadequate, but in view 

 of the size of the worm, the determination as Ascaris., and the pres- 

 ence in Marmota marmota {Arctomys niarmotd) of a large similar 

 worm, the standing of this worm may be considered in connection 

 with this latter worm, Ascaris pigmentata. 



ASCARIS PIGMENTATA von Linstow, 1897. 



Specific diagnosis. — Ascaris (p. 40) : Characterized by a dark 

 pigment occurring throughout the cuticle and the walls of the in- 

 testine and esophagus. The lips (fig. 46) have dental ridges and 

 there are inferior intermediate lips. 

 The dorsal lip is 320 [jl broad and 260 

 [X long. The lip pulp 'toward the ex- 

 ternal aspect of the worm is rouncted ; 

 that toward the internal aspect 

 divides into two parts. The lip bears 

 two double papillae. There is a gross 

 cuticular annulation at intervals of 

 30 ]^ and a finer one at intervals of 5 [jt.. 

 The esophagus is 1/10.6 of the entire 

 length. 



Male 7.5 cm. long and 950 ^ thick. The length of the tail is 1/227 

 of the entire length. The spicules are lancet-shaped and are 1.38 

 mm. long. On each side of the tail end there are 5 postanal and 

 about 22 to 25 preanal papillae. 



Female 11.4 cm. long by 1.26 mm, thick. The tail end is rounded 

 and measures 1/286 of the entire length. Eggs not developed. 



Host. — Marmota inarmota {Arctomys iinarmota^. . 



Location. — Not given; presumably intestine. 



Locality. — Konigsberg Zoological Gardens, Konigsberg, Germany. 



The presence of intermediate lips must be taken as sufficient to 

 remove this worm from the genus Ascaris. Leiper and Atkinson 

 (1914) have very properly created the new genus Kathleena for 



Fig. 4G.— Ascaris pigmentata. Lateral 

 view of head. enlarged. after von 

 Linstow, 1897. 



