PARASITIC ROUNDWORMS 



531 



55 (52) Relatively thick, heavy-bodied forms. Mouth with three lips, more 



or less conspicuous. Always oviparous. ^i 



Superfamily ASCAROIDEA Railliet and Henry 1915 . . 56 



One large dorsal and two smaller ventral lips, right and left of medial line; secondary lips 

 (interlabia) may be intercalated. Buccal capsule never present. Dorsal lip bears regularly 

 two papillae and ventral lips one each. Lips rarely greatly reduced (or absent?). 



56 (68) Polymyaria. Usually "arge opaque species 57 



For discussion of term Polymyaria see page 515. 



57 (67) Lips prominent. No ventral sucker in male. 



Family ASCARIDAE Cobbold 1864 . . 58 



Male usually has two spicules. Female with abruptly conical posterior end. 



Type genus Ascaris Linnaeus 1758. 



No fringes or tentacles on the lips, A large and complex group. Differentiated usually on 

 the basis of the form of the lips which present many modifications in minor details. 



A number of forms have been recorded under the name Ascaris which are so inadequately 

 described that their exact systematic position must depend on their rediscovery and further 

 study. Such are: 



Ascaris longa Leidy 1856 of which a single female specimen was taken from the intestine 

 of the wood ibis in Georgia. 



Ascaris penita Leidy 1886 from the intestine of the terrapin. 



Ascaris cylindrica Leidy 1849 from the intestine of Helix allernata in Pennsylvania. 



Ascaris entomelas Leidy 1851 from the lungs of Rana halecina, which the description says 

 is "not Ascaris nigrovenosa Zeder" ( = Angiostoma nigrovenosum q.v.). 



Ascaris tenuicollis Rudolphi 1819, from the stomach and intestine of Alligator mississippi- 

 ensis or encysted on viscera. Reported frequently. 



Probably most of these do not belong hi the genus Ascaris in the strict sense and very likely 

 not in the family of the Ascaridae as at present denned. These species are not well known 

 and often determinations have evidently been based on general factors that are not truly 

 diagnostic. 



58 (59) Lips relatively small, without intermediate lobes; dental plates with 



serrate edges on inner margins. 



Ascaris lanceolata Molin 1860. 



Male 20 to 25 by 0.5 mm.; female 25 to 40 by 0.8 mm. 



Lips much like those of Heterakis. Tail of male with 

 oval groove on ventral surface, and parallel longitudinal 

 furrows on dorsum; lateral to these merely cuticular folds 

 (weakly developed alae?). Papillae: about 19 preanal 

 and 12 postanal with one row of long papillae in an arc. 



In stomach of Alligator mississippiensis. Georgia. 



FIG. 824. Ascaris lanceolata. Dorsal lip, inner aspect. X 80. 

 Ventral view of tail of male. X 6. (After von Drasche.) 



59 (58) Lips well developed; with intermediate lobes or interlabia. . . 60 



60 (64) With serrate dental plates on inner border of lips 61 



6 1 (62, 63) Tail of male with 6 pairs of postanal papillae. 



Ascaris sidcata Rudolphi 1819. 



Male 35 mm. long; female 97 to 100 mm. long. 

 Body attenuate anteriorly, distinctly ringed. Lips 

 very large, hexagonal; lobes indistinct; interlabia 

 very small. TaU of male with 6 postanal papillae 

 and many (64) preanals. Bursa broad. Eggs 

 irregularly elliptical, large. 



Reported in 1887 by Leidy from the stomach of 

 terrapin, Pennsylvania. 



FIG. 825. Ascaris sidcata. Dorsal view of lips, and pos- 

 terior end of male. Magnified. (After Stossich.) 



