34 " ENDEAVOUR " SCIENTIFIC RESULTS. 



base of the ray there are 8 such series. Aetinal interradial 

 areas large, covered by the transverse series of squarish, 

 scarcely overlapping plates ; these plates have the paxilla 

 stalk reduced to an oval knob, but the spinelets are long, 

 numerous and flaring. Adambulacral plates more than 70, 

 wider than long ; those nearest the mouth are about 2 mm. 

 wide by a millimeter long ; furrow margin with 3, or usually 

 4, slender, blunt, somewhat flattened spines of which the 

 middle one or two are longest and may be 2 mm. long ; outside 

 of this series are three or four parallel series of similar but 

 smaller spines ; the whole plate is thus fairly well covered by 

 15-20 spines, the marginal ones largest, the outermost like 

 those on the aetinal plates. There are no pedicellarise. 

 Oral plates conspicuous, swollen ; each bears a curved ridge 

 5 mm. long, carrying a double series of spines ; these ridges 

 lie with concave surfaces together, so that although in contact 

 distally and proximally, they are well separated at the middle ; 

 the spines at the distal end are like the spines on the aetinal 

 plates but become longer and stouter proximally and at the 

 tip of the jaw are larger than any of the adambulacral spines. 

 Colour, light yellowish-brown or dirty yellowish. Five 

 specimens. 



The previously known species of this genus are from the 

 North Atlantic, from the Pacific, west of the southern point 

 of America, and from the Moluccas. The discovery of this 

 fourth species south-east of Australia is therefore of great 

 interest. There is little reason to doubt that it is a Mimaster, 

 but it is easily distinguished from the previously known 

 species by the shape of the rays, and by the adambulacral 

 armature. In the appearance and position of the madreporic 

 body, the Australian species resembles M. cognatus, the South 

 American species ; in the North Atlantic species M. tizardi, 

 the madreporic body is concealed by paxillse. The genus is 

 a perplexing one and its real relationships are still obscure. 



Locs. — South of Gabo Island, Victoria, 200 fathoms. This 

 specimen has been selected as the holotype. 



Between Gabo Island, Victoria, and Disaster Bay, New 

 South Wales, 50-100 fathoms. 



Genus Nectria, Gray. 



Nectria ocellata, Perrier. 



Nectria ocellata, Perrier, Arch, de Zool. exp. et gen., v., 

 1876, p. 4. 



This is a nice series of twenty-two specimens, the smallest 

 having R = 1 7 nnii . and the largest, R = 1 30 mm. In the latter 



