Order COMATULIDA A. H. Clark 



Comatulida A. H. CLARK, Proc. Biol. Soc. Washington, vol. 21, 1908, p. 135 (ordinal name sug- 

 gested to cover the recent coinatulids and their fossil relatives, including Uintacrinus); Proc. 

 U. S. Nat. Mus., vol. 34, 1908, p. 209 (internal classification); pp. 276, 277 (used as an ordinal 

 name covering all comatulicls); vol. 35, 1908, p. 120 (used as an ordinal name covering all 

 cornatulids); Proc. Biol. Soc. Washington, vol. 22, 1909, p. 174 (divided into Comatulida 

 Innatantes, Comatulida Oligophreata, and Comatulida Macrophreata) ; Proc. U. S. Nat. 

 Mus., vol. 38, 1910, p. 115 (systematic position); p. 116 (includes Comatulida and Penta- 

 crinitidae; phylogenetic position); p. 117 (division into 2 groups, Comatulida and Pentacrini- 

 tidae; phylogenetic history); p. 118 (development of the calyx); p. 214 (history; significance 

 of the loss of the larval column); vol. 40, 1911, p. 6 (45 species representing 7 families on the 

 African coasts) ; Crinoids of the Indian Ocean, 1912, p. 43 (key to the suborders) ; p. 288 (of 

 Bather, 1898; on the coral reefs at Blaking Mati " the most striking forms are numberless 

 Antedonidae") ; Journ. Washington Acad. Sci., vol. 5, No. 4, 1915, pp. 126-134 (bathymetrical 

 range; phylogenetic and paleontological significance); Die Criuoiden der Antarktis, 1915, 

 p. 110 (diagnosis; geological, geographical, bathymetrical, and thermal ranges); Amer. Jour, of 

 Science, vol. 40, 1915, p. 62 (dominant section of the Peutacrinitidae in the recent seas); p. 67 

 (detailed discussion of the bathymetrical range) ; Smithsonian Miscell. Coll., vol. 65, No. 10, 

 1915, pp. 9 and following (phylogenetical study). 



Comatulids SPRINGER AND CLARK, Zittel-Eastman's Paleontology, 1913, p. 228 (phylogenetic 

 definition); p. 234 (diagnosis and relationships). 



Diagnosis. Pentacrinites in which basals, usually but not always metamor- 

 phosed into a rosette, are present, and the column is either entirely absent, or is dis- 

 carded after the formation of the first nodal columnal which remains permanently 

 attached to the calyx. 



Geographical range. Occurring in all oceans and seas, excepting the Black Sea 

 and the Baltic. 



Bathymetrical range. From between tide marks down to 5,301 meters. 



Thermal range. From the very warm waters of the intertidal zone of the Tropics 

 down to -1.85 C. 



Remarks. It is not difficult to draw up a systematic arrangement for the recent 

 crinoids which is quite satisfactory when recent forms only are considered. But as 

 soon as an attempt is made to harmonize such a classification with a classification 

 based on the numerous fossil types difficulties at once appear. For the comatulicls 

 are in reality only a single minor offshoot from the pentacrinite stem which in the 

 recent seas has become so enormously diversified as to represent in itself alone a 

 whole order with well circumscribed suborders and minor divisions. 



The comatulids furnish one of the best examples of a small and insignificant 

 twig from a side branch of a phylogenetic tree suddenly becoming the main branch 

 and developing intricate ramifications in the nature of brauchlets, twigs, and minor 

 divisions which almost completely obscure what appeared to be, in the past, the 

 mportaut branches. 



The late Mr. Frank Springer and I, at the request of the late Dr. Charles R. 

 Eastman, prepared the section on the Crinoidea for the edition of Zittel-Eastman's 

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