540 BULLETIN 82, UNITED STATES NATIONAL MUSEUM 



pinnules are 9 mm. long, weak, and composed of 17 segments, which are mostly about 

 as long as broad. The pinnules succeeding gradually increase in length and become 

 more slender, the distal pinnules being 11 mm. long, slender, and composed of 23 

 segments, which become twice as long as broad terminally. PI tapers with moderate 

 rapidity in the proximal third, being very slender and delicate from that point onward. 

 P 2 tapers very uniformly and gradually and hence appears stouter than PI. P 3 

 tapers even more gradually than P 2 and is the longest and stoutest pinnule on the arm, 

 though it is not especially noticeable as such. 



The other specimen from Sagami Bay (No. 9300) is a badly broken example with 



about 20 arms. 



Abnormal specimen. In an example of this species from Kagoshiina Bay, Japan, 

 an arm arising on the inner side of an external IIIBr axillary divides at the sixty- 

 fourth brachial (see Part 2, p. 144, fig. 1027, pi. 11). This axillary ossicle bears a 

 pinnule on the left side. On its distal faces it bears two brachials, that on the right 

 side bearing a pinnule externally, that on the left with none. Each of these brachials 

 is followed by a syzygial pair that, like the ossicles immediately preceding, are in- 

 teriorly united. The syzygial pah- of the left side bears a pinnule on its interior distal 

 angle. The following brachials on each branch of the arm are normal and bear pin- 

 nules alternately as usual, except that the pinnule of the second brachial beyond the 

 syzygial pair on the left side is only visible in ventral view, being forced from its 

 normal position by the basal segments of the pinnule of the left syzygial pair, which 

 have grown fast to its lateral border. 



In a dorsal view it is seen that the left arm continues the arm anterior to the axil- 

 lary forward almost in a straight line, while the right branch turns off at a considerable 

 angle. This is especially evident from an examination of the ambulacral groove on 

 the ventral side of the arm. 



Remarks. In 1918 I included stylifer in the synonymy of Dichrometra ddderleini. 

 It seems, however, to be quite distinct from that species. In stylifer P 3 is one-third to 

 one-half again as long as P 2 , is composed of 16-25 segments, and is much stouter and 

 stiffer than any of the other proximal pinnules. In ddderleini P 3 is little, or even not 

 at all, longer than P 2 , is composed of 25-29 much elongated segments, and is not 

 especially stout or stiff. 



Localities. Albatross station 4929; in Colnett (or Vincennes) Strait; northeastern 

 point of Yaku Shima bearing N. 16 W., 10 miles distant (lat. 3012'30" N., long. 

 13043'00" E.); 153 meters; bottom temperature 23.78 C.; bottom, broken shells, 

 coral, and pebbles; August 15, 1906 [A. H. Clark, 1907, 1908, 1912, 1918] (1, U.S.N.M., 

 22645). 



Kagoshima Bay; U. S. Exploring Expedition [A. H. Clark, 1908] (1, U.S.N.M., 



35257). 



Sagami Bay, between Ito and Hatsushima; about 150 meters; Doctor Haberer, 

 March 1903 (2, Munich Mus., original Nos. 4219 and 9300). 



Geographical range. Southern Japan from the Korean Straits to Sagami Bay. 



Bathymetrical range. Littoral and down to 153 meters. 



Thermal range. One record, 23.78 C. 



History. Under the name of Antedon stylifer this species was first described by 

 me in 1907 from a specimen dredged by the Albatross at station 4929. 



