DRACIIIOPODA. / 



8. TerehrnlulidfP. 1. Terebrat\ila. 2. Ilypothyris, 3. Pen- 

 tamcrus. 4. Camerophoria. !). Uncites. 



I). Spiriferida;. 1. Spirifer. 2. Atrypa. 3. Martinia. 4. Stri- 

 {joccphalus. 



10. Thecideidec. 1. Thecidia. 



In 1847 M. (I'Orbigny {Ann. Sci. Nat. 1847 ; PaMont. Fr«nf. 

 Terr. Cr^t. iv. and Cours EMmentaire de PaUontologie, 12mo. 

 p. 80, 1849) proposed the following arrangement : — 



Order I. Brachiopodes brachides (Brachida). 



1. Brachides propre. 



Fam. 1. Lingulida. 1. Lingula. 2. Obolus. 



2. Calceolidce. 1. Calceola. 



3. ProductidcB. I. Productus. 2. Chonetes. 3. Leptsena. 



4. OrthlsidcB. 1. Strophoraena. 2. Orthisina. 3. Orthis. 



5. Rhynchonellidce. 1. Ilemithyris. 2. Rhynchonella. 3. Stri- 

 gocephalus. 4. Porambonites. 



6. UncitidcE. 1. Uncites. 2. Atrypa. 3. Pentamerus. 



2. Semibrachides. 



1. SpiriferidcB. 1. C^Ttia. 2. Spirifer. 3. Spiriferina. 4. Spi- 

 rigerina. 5. Spirigera. 



2. Magasidat. 1. Magas. 2. Terebratulina. 



3. TerebratulidcE. 1 . Terebratella. 2. Terebrirostra. 3. Fissi- 

 rostra. 



4. Orhiculida. 1. Siphonotreta. 2. Orbicella. 3. Orbicu- 

 loidea. 4. Orbicula. 



5. CranidcB. 1. Crania. 



Order II. Brachiopodes cirrides {Cirrhidce). 



1. Thecidce. 1. Megathiris. 2. Thecidea. 



2. Caprinida. 1, Hippurites. 2. Caprina. 3. Caprimila. 

 4. Caprinella. 



3. Radiolid<B. 1. Radiolites. 2. BiradioUtes. 3. Caprotina. 



In 1848 Dr. Gray {Ann. ^- Mag. N. H. 1848, ii. p. 435 ; 

 Translated Wiegm. Arch. 1849, 98, and Lov^, Arsh. 1845-1849, 

 213) proposed the following arrangement : — 



Brachiopoda. — Subclass 1. Ancylopoda. 



The oral arms not extensile, or only at the tip ; on fixed 

 shelly supports, or in grooves in the under or ventral valves ; the 

 mantle is adherent to the shell, the substance of the shell being 

 pierced with numerous minute perforations, which are pervaded 

 by the processes of the mantle. 



