GASTEROPODA. 249 



Sub-genera. Proto, Defr., P. catliedi'alis, PI. IX., Fig. 3, 

 apertmre truncated below. 



Mesalia, Gray, M. sulcata (var.), PI. IX., Fig. 2. Greenland 

 — South Africa. 



Fossil, Eocene. Britain, France. 



C^CTJM, Fleming. 



Synonyms, Corniculina, Miinster. Broclius, Bronn. Odontl- 

 dium, Phil. 



Tyjoe, C. trachea, PL IX., Fig. 5. Young species. Fig. 6. 



Shell at first discoidal, becoming decollated when adult; 

 tubular, cylindrical, arched; aperture round, entii'e; apex 

 closed by a mammillated septum. Operculum horny, many- 

 whorled. Lingual teeth, ; uncini, 2, the inner broad and 

 serrulated. 



DistriluUon, Britain, 11 species, 10 fathoms. Mediterranean. 



Fossil, 4 species. Eocene — . Britain, Castelarquato. 



Yermettjs, Adanson. Worm-shell. 



Synonyms, Siphonium, Gray. Serpuloides, Sassi. 



Types, Y. lumbricalis, PI. IX., Fig. 7. 



Shell tubular, attached ; sometimes regularly spii'al when 

 young ; always irregular in its adult growth ; tube repeatedly 

 partitioned o£F ; aperture round ; oj)erculum circular, concayo 

 externally. 



JDistrihiition, 31 species. Portagal, Mediterranean, Africa, 

 India. 



Fossil, 12 species. Neocomian — . Britain, Franco, &c. 



? Suh-genus. Spi7vgly2:)hi(s, D&Md. S. spii'orbisDillwyn species 

 irregularly tubular ; attached to other shells, and half buried 

 in a furrow which it makes as it grows. Perhaps an annelide ? 



Petaloconchus, sculpturatus. Lea, 1843. 



Miocene, United States, St. Domingo, South Europe. 



Shell with two internal ridges running sjnrally along tho 

 columella, becoming obsolete near the apex and aperture. 



SiLIQIJAEIA, Brug. 



Etymology, siliqua, a pod. 



Tijpo, S, anguina, PI. IX., Fig. 8. 



Shell tubular ; spiral at first, irregular afterwards ; tube with 

 a continuous longitudinal slit. 



JDistrihiition, 8 species. Mediterranean, North Australia. 

 Found in sponges. 



Fossil, 10 species. Eocene — . France, &c. 



M 3 



