538 " THETIS " SCIENTIFIC RESULTS. 



wider than long, much narrower proximally than distallyj second' 

 similar but more nearly square ; third, fourth and fifth somewhat 

 hexagonal, but with three distal sides much longer than three 

 proximal; sixth, seventh and eighth plates rather pentagonal, 

 with sharp proximal angle, or somewhat heptagonal ; succeeding 

 plates triangular, or slightly pentagonal or hexagonal, about as 

 long as wide; first five or six plates clearly in contact, and they 

 may touch as far as the fifteenth. Side arm-plates very large, 

 thick and projecting distally, separating upper and under arm- 

 plates except on basal half or two-thirds of arm ; each plate 

 carries three, or sometimes four, terete, pointed spines, the next to- 

 the lowest the longest, and about half as long as a joint ; when 

 there are three spines, the third one is two or three times as far 

 above the second as the second is above the lowest ; wiien four 

 are present, the fourth is usually just above the third, and is the 

 smallest of all. Tentacle-pores conspicuous, first eight or nine 

 with scales on both sides, but further out there are seen, on distal' 

 margin of side arm-plate, only two scales, and finally only a single 

 one ; the scales never closel}' resemble the arm-spines ; first pore 

 entirely distinct from mouth-slit, with about five scales on each 

 side ; succeeding pores have five (proximally) and four (distally), 

 four and three or two, three and two, or three and one. Colour 

 (dry), pale purplish-brown above, nearly white beneath. 



3 specimens from Station 25. Off Newcastle, 42-48 fathoms ; 

 soft mud. 



4 specimens from Station 28. Off Manning River, 22 fathoms; 

 fine grey sand. 



1 specimen from Station 52. In Shoalhaven Bight, 19-20' 

 fathoms ; sand to mud. 



This well-marked species of Ophiura^'^ belongs very evidently 

 to the variabilis group, but does not seem to be closely allied to 

 any of the snecies hitherto described. While it resembles both 

 lacazei and lienosa, it is easily distinguished from either by the 

 under arm-plates, the basal upper arm-plates and arm-comb, the 

 disc plates and the huge oral shields. Jt is not nearly related to- 

 any of the species of the genus hitherto known from Australia. 



^'''I have been unable to find any flaw in Bell's reasoning (Ann. Mag. 

 Nat. Hist., (6), viii., 1891, p. 339), by which he shows that the familiar name- 

 Ophioglypha must be abandoned in favour of Ophiura, while the brittle- 

 stars included in Ophiura by Lymau, Verrill, et al. , must bear Miiller's and 

 Troschel's name Ophioderma. Koehler (Bull. Sci. France et BeJg , xii., 

 1907, p. 281 and p. 290) goes only half-way, x\s,mg Ophioderma, hxxi clinging to 

 Ophioglypha. This would be most unsatisfactory even if it were justifiable, 

 for it would leave us without a genus Ophiura. 



