A MONOGRAPH OF THE EXISTING CRINOIDS 251 



in fact they are. But their capacity is increased by the presence of corresponding 

 pits on the under surface of the radial pentagon into which the axial canals, contained 

 between the inner faces of the radials and the spouts of the rosette, open directly. 

 Carpenter said that the only comatulid in which he had found any large cavity of a 

 similar kind within the calyx is Comatula Solaris. In Comatula Solaris the radial axial 

 canal, though it terminates blindly at the top of the centrodorsal, communicates with 

 a large cavity in the lowest part of the radial, while in H. quinduplicava tins cavity 

 is outside and below the radial, between it and the centrodorsal. 



Localities. — Albatross station 5355; North Balabac Strait; Balabac Light bearing 

 S. 61° W., 16.6 miles distant Gat. 8°08'10" N., long. 117°19'15" E.); 80 meters; 

 coral and sand; January 5, 1909 [A. H. Clark, 1911, 1912, 1918] (1, U. S. N. M., 

 35104). 



Challenger station 212; Philippine Islands, off Zamboanga (lat. 6°54' N., long. 

 122°18' E.); 18 meters; sand; January 30, 1875 [P. H. Carpenter, 1880, 1884, 1888; 

 Hartlaub, 1891; A. H. Clark, 1907, 1908, 1909, 1911, 1912, 1918; Reichensperger, 

 1913] (5, B. M.). 



Siboga station 99; anchorage off North Ubian (lat. 6°07'30" N., long. 120°26'00" 

 E.); 16-23 meters; hthothamnion bottom; June 28-30, 1899 [A. H. Clark, 1918] 

 (1, Amsterdam Mus.). 



Albatross station 5139; in the vicinity of Jolo (Sulu); Jolo Light bearing S. 51° W., 

 3.6 miles distant (lat. 6°06'00" N., long. 121°02'30" E.); 36 meters; coral sand; 

 February 14, 1908 [A. H. Clark, 1908, 1912, 1918] (1, U. S. N. M., 35183). 



Albatross station 5147; Jolo (Sulu) archipelago; in the vicinity of Siasi; Sulade 

 Island (E.) bearing N. 3° E., 8.4 miles distant (lat. 5°41'40" N., long. 120°47'10" E.); 

 38 meters; coral sand and shells; February 16, 1908 [A. H. Clark, 1908, 1912, 1918]. 



Albatross; Philippine Islands; 1907-'08 [A. H. Clark, 1908] (3, U.S.N.M., 35206). 



North of central Java (lat. 5°41' S., long. 109°21' E.); November 21, 1907 

 [A. H. Clark, 1933] (1, Buitenzorg Mus.). 



Biliton; M. Korotnev, 1885 [Koehler, 1895; A. H. Clark, 1912]. 



Danish Expedition to the Kei Islands station 72; Dr. Th. Mortensen; Java Sea 

 (lat. 5°41' S., long. 105°57' E.); 35 meters; stones and sponges; July 28, 1922 (1, 

 the type specimen of H. apollo; CM.). 



Danish Expedition to the Kei Islands station 103; Dr. Th. Mortensen; Sunda 

 Straits (lat. 6°05' S., long. 105°42' E.); 52 meters; shell bottom; August 4, 1922 (1). 



Singapore; Svend Gad [A. H. Clark, 1909, 1918] (2, CM.) 



Investigator; Andaman Islands [A. H. Clark, 1912] (1, I.M.). 



Geographical range. — From the Philippines to Biliton, Java, Singapore, and the 

 Andaman Islands. 



Bathymetrical range.- — From the shoreline down to 80 meters. The average of 

 eight records is 33 meters. 



History. — This species was first mentioned by Dr. P. H. Carpenter simply as 

 "Antedon" in an article on fossil comatulids published in 1880. He said that in one 

 of the Challenger Antedons only four rays divide out of the five, the fifth remaining 

 simple and undivided as is the case with all the rays of Ophiocrinus ( = Eudiocrinus) . 

 This refers to the specimen that he later (1888) described under the name of Antedon 

 clemens. In the same paper he said that in a Challenger species of Antedon from 



