Introduction to Animal Morphology. 185 



has been found in the human bladder. 7. Tropidocereidae 

 male slender ; female sub-globose, \vith four longitudinal 

 bands ; neck with two basilar spines. 8. Cheiracanthidae 

 body armed as far as the middle with pointed lateral lamellae ; 

 head bristled, two-lipped ; penis not sheathed ; in cats, tigers, 

 alligators, &c. 9. Physalopteridse males with a winged 

 tail-vesicle filled with a clear fluid ; mouth bilabiate, papil- 

 lose outside, toothed within ; in alligators and Mammals. 



10. Ascaridse mouth with three labial lobes, and sometimes 

 touch papillae; stomach often with teeth. The penis in 

 Ascaris is thread-like, with a two-leaved sheath. A. lumbri- 

 coides is the common human round worm, also in the orang, 

 swine, &c. ; 5-11" long ; tapering to each end ; each lip has 

 many (200) papillae ; the females are largest, and, as in other 

 species, the most numerous ; the vagina opens at the anterior 

 third. A. mystax, of the cat, is winged at its head. A. acus, 

 of the gar-pike, has linear wings. A. heteroptera has inequi- 

 lateral wings. Haligmus has a spiral, sheathless penis. 



11. Oxyuridce long, with naked or spiny tails ; mouth ter- 

 minal, papillose, or lobate ; teeth pharyngeal (Passalurus), 

 oesophageal (Pharyngodon, with no penial sheath), or at the 

 junction of the pharynx and oesophagus (Heterakis). Oxyuris 

 has no teeth ; the tail is acute in the female, papillose in the 

 male. O. vermicularis is the human thread-worm. Cosmo- 

 cerca is four-lipped, and has a ventral horny plate. Tachy- 

 gonetria is viviparous. 12. Ptychocephalidce thread-like; 



1 sub-globose, with five radiating folds ; oesophagus with 



three horny grooves; in beetles. 13. Filaridce hair-like; 



mouth round ; penis thread-like, with one or two leaf-like 



iths. Filaria Medim-nsis, the Guinea worm, is viviparous, 



and begins life as a form like Urolubes ; pierces the skin of 



bathers, then develops in the cellular tissue, and may attain 



ral fret. F. cajnicinus has l>een round in 



Ainerit an monkrys. F. Initis in the human rye. F. L<>a in 



Of the polecat, is rin-ecl. 



Gongylon- n.a. i tl, . lias in front a longitudinal 



; bulbilli. 14. I.iorhyiK hiiht- mouth in the < mire 

 of a protractile- tul-r; found in iisl, 



BI 4. Acrojjhalli j>roi luclious ; penis terminal. 



