"THETIS SCIENTIFIC RESULTS. 



PHYLLACANTHUS IMPERIALIS. 



Cidarites im2Jericdis, Lamarck, Anim. s. Vert., iii., 1816, p. 54. 

 Phyllacanthus imperialis, Brandt, Prodrome, 1835, p, 268. 



One specimen from Station 54, Within Jervis Baj', 10-113 

 fathoms ; seaweed and sand. 



This specimen has the test 62 mm. in diameter, and there are 

 7 coronal plates in each column. The largest primary spines are 

 54 mm, long and 6 mm. in diameter. The neck of the primaries 

 is purplish and shining, while the collar is fawn-colour and 

 minutely roughed. The secondary and miliary spines are bright 

 brown, becoming reddish at the tips. The abactinal system is 

 •31, and the actinal system is '40, of the horizontal diameter of the 

 test. 



STEPHANOCIDARIS BISPINOSA, 



(Plate liv, fig. 1.) 



Cidarites bispijiosa, Lamarck, Anim. s. Vert., iii., 1816, p. 57. 

 Stephanocidaris bis^nnosa, A. Agassiz, Rev. Ech., Pt. 1, 1872,, 

 p. 160. 



One specimen from Station 17. Off Broughton Island, 29-48- 

 fathoms ; sand and shell to rock. 



It is impossible not to be enthusiastic over the superb specimen^ 

 of this lovely species, one of the handsomest of the CidaridfB, 

 which the "Thetis" has been so fortunate as to collect. The 

 horizontal diameter is 45 mm.; the vertical diameter is 25 mm. 

 (•55h.d.); the abactinal system measures 21-5 mm. across 

 (•48h.d.); and the actinal system, 18 mm. (^Oh.d.). There are 

 seven cox'onal plates. The longest primary is 60 mm. (1-33 h.d.). 

 There are 7io large glohiferous jjedicellarice whatever, but triden- 

 tate (similar to those of S. hatvaiensis) are fairly common; the 

 specimen is in such perfect condition that there is no possibility 

 that the large globiferous pedicellariee have fallen off since 

 it was taken. The interambulacral secondaiy spines are 

 greenish with a dark longitudinal stripe, and pinkish tips. The 

 primary spines are more or less green and purplish ; collar con- 

 spicuously spotted with pure white. The actinal primaries have 

 the conspicuous cap characteristic of the genus, and the abactinal 

 system is also like that of the original specimen, on which the 

 genus was based. This specimen confirms my previously ex- 

 pressed opinion-^^ that neither Morfcensen nor Doderlein has seen 

 a specimen of hispinosa, and it must therefore be very rare. It 



3 3 Clark— Bull. Mus. Comp. Zool., li,, 7, 1907, p. 194. 



