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Genus 1. CHILINA, Gray. 



Animal; rather large, depressed; head flattened, zoith two angu- 

 lar tentacles, having the eyes situated about the middle ; foot 

 broad, with a fold of the mantle projecting beyond it. 



Shell; ovate, inflated, with the spire sometimes turricidated ; colu- 

 mella sharply plaited ; aperture entire at the base, lip thin. 



The ChilineB are a group of mollusks peculiar to South America, dwell- 

 ing, not in stagnant water, but in running, limpid streams, not attached 

 to plants, but to fragments of rock and stones below the surface. They 

 present an interesting link between the Auricula and Lymncea, and are 

 regarded by some authors as merely a subgenus of the latter. Both shell 

 and animal are, however, peculiar. The shells are of a uniform greenish- 

 olive colour, with bands of markings, having the columella sharply plaited ; 

 and the animal presents a difference in the tentacles and in the develop- 

 ment of the mantle. 



1. ampullacea, Soioerby. 



2. bulloides, IfOrbigny. 



3. Dombeyana, Sowerby. 



4. fluctuosa, Gray. 



5. fluminea, id. 



Species. 



6. fluviatilis, Gray. 



7. gibbosa, Sowerby. 



8. major, id. 



9. ovalis, id. 

 10. Parchappii, D' Orbigny . 



11. Puelcha, D' Orbigny. 



12. robustior, Sowerby. 



13. Tehuelcha, D' Orbigny. 



14. tenuis, Gray. 



Figure. 



Chilina ampullacea. PI. 19. Fig. 105. Shell, with olive-green-spotted 

 epidermis, showing its thin columellar plait. 



Genus 2. SCARABUS, Be Montford. 



Animal; similar to Auricula. 



Shell ; ovate, with the spire obtusely pyramidal, and the whorls 

 peculiarly depressed, each forming a varix on either side, and 

 the last being sometimes abruptly turned at the base to form 

 an angle ; aperture oval, expanded, prominently wart-toothed 

 on both sides. 



