proostracum Definition

phragmocone, rhyncholite, belemnoid, aptychus, tentaculite, anaptychus, corneocalcareous, strombite, spirifer, cornu ammonis, siphuncle, galerite, baculite, epistome, hippurite, bubble shell, tooth shell, tusk shell, maxilliped, scaphopod, encrinite, entrochite, fissurella, spongiolite, planorbis, encrinital, lituite, deltidium, milleporite, paludina, rhynchonella, gnathopod, fossil, belemnite, edaphosaurus, ossean, suspensorium, epipodite, suboperculum, septomaxillary, paragnathus, cauda galli, ammonitiferous, hyostylic, scolithus, epipodium, gnathopodite, craniate, turrilite, gnathic, interoperculum, tubiporite, saxicava, keratose, sea hare, osselet, gnathite, trochosphere, boat shell, endosternite, endophragma, hemerythrin, encrinus, ventriculite, trochite, endognath, omostegite, nodosarine, surangular, loricate, inferobranchian, metapterygium, bufonite, auriculated, conchite, echinite, pholad, peritreme, haemocoel, testacean, nothosaur, preoperculum, teleosaur, orthid, lithodome, millepore, heterostracan, fossilology, stromb, melanian, tubulipore, phoronid, siphonium, zoaea, sphenotic, cephalopod, cephalochordate, madreporite, auriform, gnathotheca,