Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 7. (Budapest, 1974)

400-600 fi from anterior end. Tail with small cylindrical projections. Tail length 250 p. Spicules unevenly elongated 100 and 33 p long (Pig. 5D). The number of tail papillae was not determinable

. Female: Length 29.00-32.00 mm, maximum width 430 p.. Esophagus length 3.80-3.90 mm. Buccal cavity 102-112 x31-43 p

. Nerve ring 360-420 p from anterior end of body. Vulva opening at level of the 29-30th cuticular spines, 4.80-5.20 mm from anterior end (Fig. 5E). Tail short and pointed, 280-340 ^1 long (Fig. 5 F). Eggs 41-45 x 20-22 p. Fig. 6: Ascaris tarbagan Schulz, 1931(0rig.) Anterior extremity, en face view Rictularia species collected from small rodents in Eurasia had usually been identified as R. cristata or as R. proni

. QUENTIN (1969) dealt in details with the taxonomy and evolution of Ric tularia species. R. cristata was reported from areas adjoining Mongolia by DUBININ and DUBININA (1951 ), and by MATSHULSKY (I959). In QUENTIN ' s view R. amur en si s Schul 7, T 1926, and R. cristata are identical. The species is new for Mongolia.