MANUAL OF CONCHOLOGY. 



MONOGRAPHS OF THE FAMILIES STOMATELLIDJE, 

 SCISSURELLIDJt, HALIOTID^E, Etc. 



Family STOMATELLID^ A. Adams, 1850. 



Stomatiidce of Fischer and others, is synonymous. 



Shell either spiral, subglobose, depressed, or haliotis-shaped, or 

 non-spiral and limpet-like ; imperforate ; aperture very large, pearly 

 inside ; muscle-impression cresceutic, open in front. 



Animal with a broad foot, longitudinally divided by a median 

 line below, and tuberculate above. Muzzle broad, ending distally in 

 an oval disc, the mouth rounded ; tentacles long, pointed ; eyes on 

 short heavy peduncles outside and behind the tentacles ; epipodium 

 prominent, fleshy, with or without cirri ; frontal lobes present ; 

 mantle-edge simple or reflexed and foliated ; not slit in front. 

 Operculum small, horny, thin, multispiral, often wanting. Gill a 

 single curved plume on the left or outer side of the mantle cavity, 

 its distal third free. Verge wanting. Formula of teeth (00.1) 5. 1. 

 5 (1.00). 



A family of small, brilliantly nacreous shells closely allied to 

 Trochidse but with fewer whorls, and larger aperture. There have 

 been considerable differences observed between the animals of various 

 genera of Stomatellidce ; under Stomatella I have described the 

 animal examined by myself. 



These shells tell very clearly the story of the origin of limpet-like 

 types in the Rhipidoglossa. From Stomatella we can trace by a chain 

 of closely allied forms, the uncoiling of the spire and increase of the 

 body-whorl to Stomatia, Gena, and finally Broderipia, where some 

 species have the form of typical Patella. 



The monographic works on Stomatellidce are as follows : 



(5) 



