PEISTTAMEETTS . 235 



PEDUNCULATED. (Pedunculus, a little foot.) Attached to 

 external objects by a hollow fleshy tube, called the Peduncle. 



PEDUNCULATED CIEEIPEDES. Lam. An order consist- 

 ing of molluscs which have multivalve shells, supported on a 

 peduncle. The genera which it contains are thus distinguished : 



1. Pentelasmis. Eive valves. Pig. 34. 



2. CiNEEAS. Pive very minute valves distant from each 



other. Pig. 42. 

 8. Otion. The same, but the animal has two auricles. Pig. 

 43. The genus Palmina, Gray, has but one. 



4. OcTOLASMis. Shaped like Pentelasmis, but with 7 or 8 



valves. Pig. 41. 



5. LiTHOTETA, Pive valves, peduncle scaly, with a plate at 



the base. Pig. 39. 



6. ScALPELLTJM. Shape square, valves 13, peduncle scaly. 



Pig. 35. 

 -7. Smilitjm. Same, but the peduncle hairy. Pig. 36. 



8. Ibla. Pour valves, one pair long, one pair short, peduncle 



hairy. Pig. 40. 



9. Beismetjs. Even at the base. Pig. 38. 



10. PoLLiciPEs. Principal valves in pairs, with many smaller 

 valves at the base. This genus has been divided into 

 Pollicepes, and Capitellum, the latter of which is founded 

 upon PoUicepes MiteUus, Auct. Pig. 37 and 37*. 

 PELAGUS. Montf. A genus composed of species of Ammo- 

 nites, which have the spire covered by the last whorl, as in 

 Nautilus, and have an umbilicus. Oebtjlites. B1. 

 PELLUCID. Transparent. 



PELOEUS. Montf. Polystomella, B1. A genus of micros- 

 copic Poraminifera. 

 PELOEONTA. Oken. Neeita Peloronta, Auct. 330, 

 PENEEOPLIS. Montf. A genus of microscopic Poraminifera. 

 PENICILLUS. Brug. Aspeegillitm, Auct. 

 PENTAMEEUS. Sow. (Jlevre, pente, five ; jiepoq, mgros, part.) 

 Fam. Brachiopoda, Lam. — Descr. Equilateral, inequivalve ; one 

 valve divided by a central septum into two parts ; the other by 



