A MONOGRAPH OF THE EXISTING CRINOIDS 79 



on the cirrus segments had been overlooked, the dorsal processes bemg assumed to be 

 single spines. This error -was soon afterward detected. In a paper on the crinoid 

 fauna of the Atlantic published in 1914 I said that Analcidometra represents the genus 

 Oligometrides in the Atlantic, and the same statement was made in a memoir on the 

 crinoids of West Africa published in the same year. In two papers published in 1915 

 I said that Analcidometra is most closely related to the Australian genus Oligometrides, 

 and pointed out that it is confined to the western Atlantic. In 1916 I remarked that 

 it is most closely related to Austrometra and to Oligometrides. In my report upon the 

 unstalked crinoids of the Siboga expedition published in 1918 Analcidometra is included 

 in the key to the genera of the family Colobometridae. In this key it is paired with 

 the genus Austrometra, these two genera being distinguished from the other lO-armed 

 genera with Pa present by having the third-fifth segments of the genital pinnules 

 expanded. Analcidometra is said to have Pi much stouter than P2 and so enlarged 

 basally as to cause the second bracliial to appear like an axUlary, and the median 

 ridge on the cirrus segments very high, whereas in Austrometra Pi, though longer 

 and stouter than P2, is not exceptionally so, and the median transverse ridge on the 

 cirrus segments is of moderate height. 



Although the genus Analcidometra had been frequently mentioned from 1911 on, 

 this was the first indication of the characters by which it was distinguished from the 

 other genera of the famUy Colobometridae. The characters giver in the key were, 

 however, taken from armata as redescribed and figured by Hartlaub in 1912 and not 

 from the type species caribbea which was described before the author had seen any 

 specimens, or an adequate description, of armata. After the appearance of Hart- 

 laub's work it was assumed that caribbea was the young of armata, and not until the 

 receipt of the 18 specimens from the Caroline collection in 1933 was it reahzed that one 

 of the two large specimens of armata described by Hartlaub was in reality caribbea, as 

 is shown by his figures (pi. 7, figs. 3, 4; pi. 13, fig. 7, left). In 1921 I mentioned 

 Analcidometra as a genus confined to the West Indian region, and included it in a key 

 to the genera of crinoids represented in the Caribbean Sea and adjacent waters. 

 The characters used in this key were those of armata and not of caribbea. In a list of 

 the crinoids of the Atlantic published in 1923 I included the genus Analcidometra with 

 the single species A. armata and gave the range, which included the type locality of 

 A. caribbea, at that time stiU assumed to be a synonym. 



KEY TO THE SPECIES IN THE GENUS ANALCIDOMETRA 



o'. Pi very much stouter than P?, so much enlarged as to give the second brachial the appearance 

 of an axillary (from the Florida Straits and the Bahamas to Barbados; 5.5-64 meters'). 



armata (p. 79) 



a'. Pi shorter and less stout than Pj, though of the same character; the lower pinnules are not 

 greatly enlarged (from north of Puerto Rico to Colon ; 62 meters) caribbea (p. 84) 



ANALCIDOMETRA ARMATA (PonrUlte) 



[See vol. 1, part 1, fig. 355 (cirrus), p. 293.] 



Antedon armala PourtalIis, Bull. Mus. Comp. Zool., vol. 1, No. 11, 1869, p. 356 (description; 

 west of Tortugas, 35 fms.).— P. H. C-rpenter, Trans. Linn. See. (Zool.), ser. 2, vol. 2, 1879, 

 p. 29 (listed as an Antedon). — Bell, Proc. Zool. Soc. London, 1882, p. 532 (listed), p. 534 

 (specific formula).— P. H. Carpenter, Proc. Zool. Soc. London, 1882, 1883, p. 746 (specific 

 formula); Challenger Reports, Zoology, vol. 26, pt. 60, 1888, pp. 54, 207 (listed), p. 376 



