209 



twice as broad dorsoventrally as the proximal: opposing spine large and prominent, triangular, 

 arising from the entire dorsal surface of the penultimate segment, directed obliquely forward. 



The distal borders of the radials are even with the rim of the centrodorsal ; the IBrj 

 are short, almost entirely divided in the median line by the posterior process of the axillarv, 

 well separated interradially, not in contact basally. 



The IBr 3 (axillaries) are rhombic, all the sides strongly concave, about as broad as long, 

 vvidely separated from their neighbors. 



The 10 arms are 45 mm. long; they resemble those of C. serrata, but the distal edges 

 of the brachials, while overlapping and spinous, are much less conspicuously and more hnely 

 spinous, and lack the strongly marked longitudinal ridges running inward from each of the 

 spinous processes. 



Syzygies occur between the third and fourth brachials, again between the ninth and tenth 

 and fourteenth and hfteenth and distally at intervals of three oblique muscular articulations. 



Pj is 8.5 mm. long, moderately slender, composed of 17 — 18 segments of which the hrst 

 two are broader than long, the third is about twice as long as the median breadth, and the 

 remainder are approximately three times as long as broad, and somewhat longer distally ; the 

 third and following have slightly projecting and overlapping distal edges, this increasing distally. 

 P a is much smaller and more slender than P x , 4 mm. long with 1 1 segments of which the first 

 two are short, the third is half again as long as broad, and the following rapidly become 

 elongated ; the segments have moderately produced spinous overlapping distal edges. P„ is 

 from 3.0 mm. to 4.5 mm. long with about 11 segments; it tapers less rapidly than P, and 

 thus appears stouter, especially distally. P i is similar to P„, but slightly longer and slightly 

 stouter. The distal pinnules are very slender, 7 mm. long with 16 — 17 segments which have 

 slightly spinous distal edges. 



5. Compsomctra serrata (A. H. Clark). 



A. H. CLARK. Buil. Mus. Comp. Zo<">l., vol. 51, 190S, N°S, p. 240, pi. 1, fig. 4 {Antedon serrata). 



Proc. Biol. Soc. Washington, vol. 21, 190S, p. 131 {Compsometra serrata). 



Proc. U.S. National Museum, vol. 34, 190S, p. 316 [Compsometra serrata). 



Vidensk. Medd. fra den naturhist. Forening i Kobenhavn, 1909, p. 192 {Compsometra 



serrata). 



6. Compsometra lovcni (Bell). 



Wright. Proc. Roy. Irish Acad. [2], vol. 2, 1877, p. 754 (? Kallispongia arekeri). 

 BELL. Proc. Zool. Soc. London, 1882, p. 534 {Antedon lovéni). 



"Alert" Report 18S4, p. 157, pi. 10, figs. B, Ba, b {Antedon pumila; based upon the 



same specimens as the preceding). 



Proc. Linn. Soc. New South Wales, vol. 9, 1885 [1884], p. 497 {Antedon pumila). 



P. H. Cari'ENTER. "Challenger" Reports. Comatulae, 1888, p. 56, paragraph 3 {Antedon lovéni; 



Antedon pumila). 

 Bell. Ann. and Mag. Nat. Hist. [6], vol. 3, 1889, p. 392 {Antedon pmnila, part). 

 Whitelec;ge. Journ. Roy. Soc. New South Wales, vol. 23, 1889, p. 197 {Antedon pumila). 

 P. H. Carpexter. Proc. Roy. Soc. Victoria (N. S.), vol. 2, 1890, p. 135 {Antedon pumila). 



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