A MONOGRAPH OF THE EXISTING CRINOIDS 343 



St. Helena; 2 miles off Bay Point; 480 meters; Dana, February 24, 1930 [Gisl6n, 

 1933]. 



Geographical range.— From the Yucatan Bank, the Florida Keys, northern Cuba, 

 and the southern Bahamas eastward and southward along the Antillean chain to Bar- 

 bados and Grenada; also St. Helena. 



Bathy metrical range. — From 139 to 707 meters. 



Thermal range.— From 8.33° to 18.20° C. 



History.— In a paper dated December 26, 1867, but distributed early in 1868, 

 Count Louis Francois de Pourtales described Comatula brevipinna as follows: 



Ten arms. Mouth and anus not seen in the only specimen examined. About 15 cirrhi, with 

 the same number of long articulations. Seven or eight articulations to every syzygium. The two 

 radials are visible, and have, as well as the axial radials and the two first brachials, a smooth tubercle 

 in the middle. The same pieces are denticulated on the sides, the denticulations meeting those of 

 the collateral radials and brachials, so as to close up the angle between them. A row of very small 

 tubercles on the proximal border of the radials and radial axials. The articulations of the arms 

 somewhat imbricate. First pinnule longest with about twelve joints. The other pinnules very- 

 short, having only five or six joints in the middle of the arm, but lengthening out again near the end 

 of the arm, the last ones being tipped with a hook, like the cirrhi. 



In the only specimen obtained one of the arms is abortive and divided into three very short 

 branches; to compensate, one of the arms of the next pair is divided into two from its origin. 



In 270 fathoms off Havana [Corwin station 2]. 



In another paper published in November 1869 Count Pourtales said that Antedon 

 brevipinna Pourt. [Comatula brevipinna Pourt.] was not obtained again since the first 

 specimen was dredged in 1867. 



In a paper published on December 14, 1878, Pourtales described Antedon granulif era 

 in the following terms: 



Twenty arms. Centrodorsal piece hemispherical and covered with cirrhi in the young, but 

 becoming bare and flattened in the middle at a later period, showing more or less obsolete traces of 

 the sockets. At the junction with the radials it has five knobs projecting into the interambulacral 

 spaces. Cirrhi in two or more rows, with fifteen to eighteen joints, longer than broad, except the 

 two or three first ones, which are very thick. Penultimate with a spine. First radials entirely 

 concealed, very firmly connected with one another and with the rosette. Second radials [IBrJ 

 thin ; axials very depressed, pentagonal. First brachials rather flattened and in close lateral contact. 

 Three brachials between primary and secondary axials, one between secondary and tertiary. Syzygia 

 rather irregular, nine, ten, or more joints apart. Sometimes there are syzygia in the first and second 

 joints of the arms. The joints are somewhat saddle-shaped, with a deep notch for the insertion of 

 the pinnules and a point on the proximal border fitting into a shallow notch of preceding joint. About 

 the middle of the arm they are frequently, but not always, ornamented with bead-like tubercles, of 

 which the middle one is largest. These tubercles are also found generally on the radials. First 

 pinnule longest and very broad on first brachial, thence diminishing in length toward extremity. 

 The joints of the pinnules are very broad. Mouth central. Spread 20 to 25 cm. 



[Blake] Station 45. Lat. 25°33' N., Long. 84°21' W. 101 fathoms. 



In his memoir on the genus Actinometra published in 1879 Dr. P. H. Carpenter 

 said that he was unable, on the basis of the published description, to assign Comatula 

 brevipinna either to Antedon or to Actinometra. 



In a preliminary report upon the comatulids of the Blake expedition published on 

 October 1, 1881, Dr. Carpenter mentioned Actinometra granulif era as a species in 

 which there is a considerable amount of anambulacral plating in the anal area; he said 



