REPORT ON THE CRTNOIDEA. 345 



3. Actinometra trichoptera (Valenciennes), Miill., sp. (PI. LXIII. figs. 1-5). 



be 

 Spec ific formula — a. 3 . ( 3 ) . — . 



Comatula trichoptera, Valenciennes, MS. 

 1846. Comatula trichoptera, Miiller, Monatsber. d. k. preuss. Akad. d. Wiss. ^Berlin, 1846, p. 178. 

 1849. Comatula trichoptera, Miiller, Abliandl. d. k. Akad. d. Wiss. Berlin, Jahrg. 1847 [1849], 



p. 257. 

 1862. Comatula trichoptera, Dujardin and Hupe\ Hist. Nat. des Zoophytes, fichinodermes, 



Paris, 1862, p. 205. 

 1879. Actinometra trichoptera, P. H. Carpenter, Trans. Linn. Soc. Lond. (Zool.), ser. 2, 1877 



[1879], p. 27. 

 1882. Actinometra trichoptera, Bell, Proc. Zool. Soc. Lond., 1882, p. 535. 

 1882. Actinometra trichoptera, P. H. Carpenter, Ibid., p. 747. 



Centro-dorsal a relatively wide disk, bearing some thirty or more marginal cirri. 

 These have about sixteen joints, a few of which are longer than wide, the penultimate 

 with but little trace of au opposing spine. 



First radials scarcely visible, and the second but partially united laterally ; the rays 

 quite free and the axillary angle rather sharp. Three distichals and sometimes three 

 palmars, the axillary with a syzygy. 



Fifteen to twenty-two arms, of slightly overlapping joints, the lower ones relatively 

 short and triangular, gradually becoming longer and more quadrate. Syzygies in the third 

 and in the tenth or twelfth brachials, and then at intervals of three or four joints. 



The distichal pinnule is about 9 mm. long, and that on the second brachial but little 

 shorter. The next two or three diminish rapidly in length, but become swollen for the 

 genital glands and lose their terminal comb. The lower joints of the earlier pinnules 

 sometimes overlap rather sharply and have spinose edges. 



Mouth interradial ; disk naked. 



Colour in spirit, — light yellowish -brown, mottled with grey or darkish brown. 



Disk 9 mm.; spread 12 cm. 



Locality. — Port Jackson ; 10 to 12 fathoms. One specimen. 



Other Localities. — Port Philip ; King George's Sound. 



Remarks.- — The types of this species were brought to Paris from King George's Sound 

 by Quoy and Gaimard, and received from Valenciennes the MS. name trichoptera, which 

 was adopted by Miiller when he afterwards described them. Its range was extended to 

 Port Jackson by the Challenger, and the British Museum has since obtained examples of 

 it from Port Philip, so that it may be assumed to be common along the whole southern 

 coast of Australia. But I have never met with any form like it from the tropical seas. 

 Actinometra robustipinna from the Moluccas resembles it in the presence of a large 

 number of cirri, but is readily distinguished by the great size of its first three pinnules. 

 On the other hand there is a considerable resemblance between Actinometra trichoptera 



(ZOOL. CHALL. EXP.— PABT LX.— 1888.) OoO 44 



