112 SYNOPSIS OF AMERICAN FOSSIL BRACHIOPOBA. [bull. 87. 



Megatliyris, Eudesella, Pteroyliloios, Thecidea, etc. (ptycholoplms type), 

 and (/>) by looping" (zugolopbus) and the growth of a median, unpaired 

 coiled arm (plectolophus), as in Magellania, Terebratulina, etc.; in the 

 second (c) by the growth of two, separate, coiled extensions or arms, 

 one on each side of the median line (spirolophus), as in Liugula, 

 Crania, Discinisca, Rhynchonella, Leptiena, Davidsonia, Spirifer, Athy- 

 ris, Atrypa, etc. 



REFERENCES. 



1. Beecher, C. E., 1893: Revision of the faini]ie.s of loop-liearing Brachiopoda. 

 Trans. Conn. Acad., Vol. IX. 



2. Beecher, C. E., 1893: The tlevelopment of Terehratdlia ohsohta Dull. Trans. 

 Conn. Acad., Vol. IX. 



3. Beecher, C. E., and J. M. Clarke, 1889: The development of some Silurian 

 Brachio])oda. Mem. N. Y. State Museum, \o\. I, No. 1. 



4. Beecher, C. E., and Charles Schuchert, 1893: Development of the brachial sup- 

 ports in Dielasma and Zygospira. Proc. Biological Soc. Washington, Vol. VIII. 



5. Brooks. AV. K., 1879 : The development of Lingula and the systematic position 

 of the Brachiopoda. .Johns Hopkins Cniv., Chesapeake Zool. Lab. 



6. Davidson, T., 1851-1885: A monograph of the British fossil Brachiopoda. Pal. Soc. 



7. Davidson, T., 1886-1888: A monograph of recent Brachiopoda. Trans. Linn. 

 Soc, London, Vol. IV. 



8. Fischer P., and D.-P. ffihlert, 1892: R^snltats des campagnes scientifiques 

 accomplies sur son yacht par Albert l''^', Prince Souverain de Monaco. Fs. Ill, 

 Brachiopodes de I'Atlantique Nord. 



9. Hancock, A., 1858: On the organization of the Brachiopoda. Phil. Trans., 

 Vol. CXLVIII. 



10. Kovalevski, A. O., 1874: Observations on the development of Brachiopoda. 

 Proc. Imp. Soc. Amateur Naturalists, etc., held at the University of Moscow, 11th 

 year. Vol. XIV. 



11. Morse, E. S., 1873: On the early stages of Terchratnllna ncpteiitrioiialis (Cou- 

 thouy). Mem. Boston Soc. Nat. Hist., Vol. II. 



12. Miiller, F., 1860: Beschreibung einer Brachiopodenlarve. Archiv Auat. 

 Physiol., Jahrg. 1860. 



