PULMONATA — BASOMMATOPHORA 



439 



Fam. 1. Auriculidae. — Breathing organ a pulmonary sac 

 or true lung ; shell spiral, conoidal, internal partitions usually 

 absorbed, aperture more or less 

 strongly toothed. Jurassic . 



Fig. 292. — Examples of the Avricididae : 

 A, Auricula Judae Lam., Borneo; B, 

 Scarabus Lessoni Blainv., E. Indies; 

 C, Cassidula mustelma Desh., N. Zea- 

 land; D, Melampus castaneus Miihlf., 

 S. Pacific; E, Pedipes quadridens Pfr., 

 Jamaica. 



Genera: Auricula^ Carychiiim, 

 Scarabus^ Alexia, Tralia, Pleco- 

 trema, Cassidula, Melampus, 

 Leuconia, Pedipes (Fig. 292). 

 Fam. 2. Otinidae. — ^hQll 

 auriform, spire very short. 

 Genera: Otina, Camptonyx, — 

 Recent only. 



Fam. 3. Amphiholidae. — A 

 pulmonary sac on right side of 

 neck, eyes almost pedunculate, 

 shell turbinate, rudely sculpt- 

 ured, operculate. — Recent. 

 Genus, Amphibola (Fig. 293) ; 

 subg. Ampullarina. 



Fam. 4. Limnaeidae, — Pulmonary sac protected by an exter- 

 nal lobe; shell variable, fragile. Jurassic . (i.) Ancylinae, 



shell more or less limpet-shaped. Genera : Ancylus, Grundlacliia, 

 Latia. (ii.) Limnaeinae, shell spiral. Genera: Limnaea, Amphi- 

 peplea, Erinna, Lantzia, PompTiolyx, ChoanompJialus (with 

 Carinifex^. (iii.) Planorhinae, shell sinistral, spire flattened or 

 elevated. Genera : Planorhis, Isidora (^ = Bulinus). 



Fam. 5. Physidae. — Mantle more or less reflected over the 

 shell (radula. Fig. 141c, p. 235) ; shell sinis- 

 tral, lustrous. Jurassic . Genera : PAysa, 



Apleeta. 



Fam. 6. Chilinidae. — Lobe of pulmonary 

 sac large, tentacles broad ; shell ventricose, 



rather solid ; columella plicate. Miocene . 



Single genus, Ohilina. 



Sub-order II. Stylommatopliora. — Two 

 pairs of retractile tentacles (except in Janella^, eyes at the tip 

 of the upper pair, male and female orifices united (except in 

 Vaginulidae and Onchidiidae), no distinct osphradium. 



Fam. 1. Testacellidae. — Animal carnivorous, slug-like or 

 spirally coiled, no jaw (whence the name Agnatha, often given 



Fig. 2'dZ.— Amphibola 

 avellana Chem. 



