A MONOGRAPH OF THE EXISTING CRINOIDS 409 



flattened, outer sides. The inner side of the first syzygial pair (composed of bra- 

 chials 3 + 4) may also show traces of flattening. 



Arms 11-15 in number, about 65 mm. long, consisting of about 70 shortly 

 triangular brachials, the lower ones rounded; the later brachials gradually become 

 compressed laterally and develop a forward-projecting spine which overlaps the base 

 of the next segment and is much more distinct in some individuals than in others. 



The first syzygy is between brachials 3+4 and the next is between the eleventh 

 and twenty-first brachials. The distal intersyzygial interval is from 4 to 9 (usually 

 5 or 6) muscular articulations. 



PI and P a are short and stiff, not more than 5 mm. long, and consist of 8 or 9 

 elongated segments. P 2 and P b are much stouter, reaching 10 mm. in length, with 

 about 12 rounded segments. The pinnules following are of about the same length 

 with broader and more flattened basal segments which are sometimes slightly 

 carinate. There are 6 or 8 pinnules of this character on either side of the arm, but 

 the greater width of the lowest segments is distinct for some distance farther, and 

 the length of the pinnules does not increase. 



The disk, which is 7 mm. in diameter, is scarcely at all plated, and the brachial 

 ambulacra are but slightly plated. The genital glands, contained in the expanded 

 portions of the large lower pinnules, are protected by an imperfect pavement of ill- 

 defined plates that supports the ambulacra! skeleton. This last is not well differ- 

 entiated; the covering plates are tolerably distinct, resting on a continuous calcareous 

 baud which is scarcely segmented into side plates except on some of the later pin- 

 nules. The position of the side plates, however, is indicated by the sacculi, which 

 are also abundant on the brachial ambulacra and extend down on to the outer part 

 of the disk. 



In alcohol the calyx is nearly white and the arms a darkish purple. 



Dr. Clemens Hartlaub noted that in a specimen from Sydney in the Gottingen 

 Museum the position of the first syzygy varies from between brachials 3 + 4 to between 

 brachials 4 + 5 or even 6 + 7. 



The specimen from Port Phillip in the British Museum is a beautiful example. 



Two of the specimens from the "Pacific Ocean" (presumably Sydney) collected 

 by the United States Exploring Expedition in the National Museum have 14 and 20 

 arms; the one in the Museum of Comparative Zoology at Cambridge, Mass., has 

 15 arms 60 mm. long and the cirri 50 mm. long. 



Dr. Wilhelm Minckert noted that in a fully grown individual, for which he gave 

 no locality, he found one postradial series with small ossicles regenerating from a 

 radial. The other four postradial series were normal. 



Localities. Eleven miles eastsoutheast of the Clarence river mouth, New South 

 Wales; 64-66 meters; Endeavour, 1909-'14 [H. L. Clark, 1916] (6, M. C. Z., 716). 



Eight miles east of Sandon Bluffs, New South Wales; 64-73 meters; Endeavour, 

 1909-'14 [H. L. Clark, 1916] (19, M. C. Z., 726). 



Broughton Island [A. H. Clark, 1911] (2, U.S.N.M., 35502; Australian Mus.). 



Thetis station 28; off Manning river; 40 meters; fine gray sand; February-March 

 1898 [H. L. Clark, 1909; A. H. Clark, 1911] (49, U.S.N.M., 35569; Australian Mus.). 



Thetis station 12; off Cape Three Points; 40-62 meters; sand; February-March 

 1898 [H. L. Clark, 1909; A. H. Clark, 1911] (14, M. C. Z., 373, 375; Australian Mus.). 



724008 17 27 



