Craniella (Eblert, 1888. 

 Cardiuocrauia Waageu, 1885. 

 Aucistrocrania Dall, 1877. 



CranopsicS Dall, 1871 (not A. Adams). 

 Craniscus Dall, 1871. 



Si])bonaiia (^ueusteclt, 1851 (uot 

 Sowerl)v). 

 Pholidops Hall, 18<i(). 



.scHucHKia] CLASSIFICATION OF PROTREMATA. 131 



Superfaiuily CRANIACEA Waagen, 1885.' 



Gasteropeguiata Waagen, 1885. 



Cemented calcareous Neotremata without i)edicle or anal openings 



at niatiu'itv. 



Family OKANIIDyE King, 1810. 



OrbiculiP DeshayeH, 1830; Craniadic Gray, 1810. 



Oraiiiacea with the pedicle functional i)robably only during uepionic 

 growth. 



Crania Retzius, 1781. 



NuiuniulTis Stoeboeus, 1732. 



OHtracite.s IJtsiith, 1776. 



Criopiis Poll, 1791. 



Ciiopoderma Poli, 1795. 



Orbicula Cuvier, 1798 (not Howerby, 



1830). 



Orbicularius Dumeril, 1806. 



Cianiolit.'s Scblotbeim, 1820. 



,^- • r„ . 1000 / i T I Crauiops H;ill, 1859. 



Discina lurtou, 1832 (not Lamarck, , '' 



^^iQs^ Pseudocrania McCoy, 1851. 



Criopododeruia A-assiz, 1846. Paheocrania QuenBtedt, 1871. 



Cbouiopora .Scbauiotb, 1854. | 



Order PROTREMATA Beecher, 1891. 



Derived, articulate Brachiopoda, with tlie pedicle opening restricted 

 to the ventral valve througliout life or during early growth. Prodel- 

 tidium originating on tlie dorsal side of the body wall in the cephalula 

 stage, and later anchylosed to the ventral shell, thus initiating the 

 development of a deltidiuni. Pedicle aperture modihed by the delti- 

 dium. Brachia unsupported by a calcareous skeleton except in the 

 Pentameracea where there are crura. 



Superfaraily STROPHOMENACEA Schuchert, 1896. ^ 



Lincicardines (partiiu) and Deuticardiues (partiui) Bronu, 1862; Apbaneiopegniata 

 (partim), Prodnctacea, CoiJiIIiop.sida, andKaiupylopegniata(partiin) Waageu, 1883; 

 Eieutherobrancbiata (partim) Neumayr, 1883; Cryptobrachia (partim) Gray, 1848; 

 Thecacea Scbuchert, 1893. 



Primitive Protremata without spondylia and cruralia. 



Family KUTORGINID.E Schuchert, 1893. 



Primitive Strophomenacea with incipient cardinal areas, great del- 

 tliyrial opening, and very rudimentary articulating processes and 

 deltidium. 



Kutorgina Billings, 18G1 (emend ^Schizopholis Waagen, 1885. 

 Walcott). I 



'The writer believes that when the young growtli .stages of Crania are .studied it will be shown 

 that tlip Craniacea have the .superfamily characters of Acrotretacea rather than those of Oiscinacea. 

 'Text-book of Paleontology, by Zittel and Eastman, 1896, p. 312. 



