390 GLOSSARY. 



Paleontology (Gr. palaios, ancient ; and logos, discourse). The science of 



fossil remains or of extinct organised beings. 

 Paleophis (Gr. palaios, ancient ; 02MS, serpent). An extinct genus of 



Snakes. 

 Paleosaurus (Gr. palaios, ancient ; sa.ura, lizard). A genus of Thecodont 



Reptiles. 

 Paleotherede (Gr. iJoXaios, ancient ; tlier, beast). A group of Tertiary 



Ungulates. 

 Paleozoic (Gr. palaios, ancient ; and zot, life). Applied to the oldest of the 



great geological epochs. 

 Paradoxides (Lat. pa/racloxv^, marvellous). A genus of Trilobites. 

 Patagium ( Lat. the border of a dress) . Applied to the expansion of the in- 

 tegument by which Bats, Fhnng Squirrels, and other animals support them- 

 selves in the air. 

 Pecopteris (Gr. peko, I comb ; jjteris, a fern). An extinct genus of Ferns. 

 Pecten (Lat. a comb). The genus of Bivalve Molluscs comprising the 



Scallops. 

 Pectoral (Lat. indv^, chest). Connected with, or placed upon, the chest. 

 Pentacrixus (Gr. penta, five ; krinon, lily). A genus of Crinoids in which 



the column is five-sided. 

 Pentamerus (Gr. penta, five; meros, part). An extinct genus of Brachiopods- 

 Pentremites (Gr. penta, five; tremo., aperture). A genus of Blastoidea, so 



named in allusion to the apertures at the summit of the calyx. 

 Perenxibranchiata (Lat. -perennis, perpetual ; Gr. hragchia, giU). Applied 



to those ^4?/?2J/ri'5z« in which the gills are permanently retained throughout 



life. 

 Perissodactyla {Gr. perissos, uneven: doMulos, finger). Applied to those 



Hoofed Quadrapeds [Ungulata) in which the feet have an uneven number of 



toes. 

 Petaloid. Shaped like the petal of a flower. 



Phacops (Gr. pihaM, a lentil ; op)s, the eye). A genus of Trilobites. 

 Phalanges {Gt. p)ho.lan:c, a row). The small bones composing the digits of 



the higher Vertebrata. Xormally each digit has three phalanges. 

 Phanerogams (Gr. pi^'y-''^^i'os, visible ; go/rnos, marriage). Plants which have 



the organs of reproduction conspicuous, and which bear true flowers. 

 Phartngobranchii (Gr. pkarugx, pharj-nx; hragchia., giU)- The order of 



Fishes comprising only the Lancelet. 

 Phascolotherium (Gr. piha.skolos, a pouch; therion, a beast). A genus of 



Oolitic [Mammals. 

 Phragmacone (Gr. phragraa, a partition ; and konos, a cone). The chambered 



portion of the internal shell of a Belemnite. 

 Phtllopoda (Gr. pliullon, leaf; andy^oz/s, foot). An order of Crustacea. 

 Pinnate (LslX. piinna, a feather). Feather-shaped; or possessing lateral pro- 

 cesses. 

 PiNNiGRADA (Lat. pi/i/ia, a feather ; gradior, I walk). The group of Carniv- 



ora, comprising the Seals and ^yalruses, adapted for an aquatic life. Often 



called Pinnipiedia. 

 Pinnule (Lat. dim. oi pinna). The lateral processes of the arms of Crinoids. 

 Pisces (Lat. piscis, a fish^. The class of Vertebrates comprising the Fishes. 

 Placoid (Gr. pjla^., a plate; eidos, form). Applied to the irregular bony 



plates, grains, or spines which are found in the skin of various fishes 



( Ela^mohra nch ii) . 

 Plagiostomi (Gr. plagios, transverse ; stoma, mouth). The Sharks and Rays, 



in which the mouth is transverse, and is placed on the under surface of the 



head. 

 Plattceras (Gr. platus, broad ; keras, horn). A genus of L^nivalve Molluscs. 

 Plattcrinus (Gr. platus, broad; krinon, lily). A genus of Crinoidea. 

 Platyrhina (Gr. platus, broad ; rhines, nostrils). A group of the Qua.druniana.. 

 Platysomus (Gr. platus, wide ; sorrua, body). A genus of Ganoid Fishes. 

 Pleistocene (Gr. pleistos, most ; Tcainos, new). Often used as sj-nonymous 



with " Post-Pliocene." 



