540 " THETIS " SCIENTIFIC RESULTS. 



The upper arm-plates in large individuals are often broken into 

 two or more plates. There are usually five arm-spines, bub 

 occasionally six are found on the basal joints. 



AMPHIPHOLIS AUSTRALIANA,!^ sp. nov. 

 ^Plate lii, figs. 1-3). 



Diameter of disc, 3"4mm.; length of arm, 8 (?) mm Di.sc 

 flat, circular, covered by 100-150 coarse scales, in addition to 

 the conspicuous radial shields, which are half as wide as 

 long, in close contact along their inner margins, and strongly 

 convex on the outer side. Upper arm-plates about as long as 

 wide, squarish or pentagonal, with a wide angle proximally, and 

 corners usually more or less rounded ; even at base of arm they 

 are widely separated from each other. Each interbrachial space 

 below, completely covered by about forty-fifty scales. Oral 

 shields rather triangular, with a sharp angle inward and a 

 strongly convex distal margin about as wide as long. Adoral 

 plates large, three times as long as wide, somewhat wider at outer 

 than at inner end. Oral plates very small and indistinct. Oral 

 papillae three on each side, distal one wider than other two 

 together. Under arm-plates ixiore or less pentagonal; first one 

 about as wide as long, hardly one-fourth as large as second, 

 in contact with it ; second and succeeding plates longer than wide, 

 well separated from each other. Side arm-plates large, meeting 

 broadly both above and below, the distal margin somewhat 

 flaring ; each plate carries three (at base of arm sometimes four) 

 spines, subequal or middle one shortest; uppermost slender, terete 

 and pointed ; middle one thickened at base ; lowest like upper- 

 most, but less slender ; at base of arm uppermost spine equals or 

 may exceed a joint, but is usually much shorter. Tentacle-scales 

 two, relatively large, the one on side arm-plate noticeably larger 

 than the one on under arm-plate. Coloui', pale yellowish or whitish, 

 apparently without light spots on outer ends of radial shields. 



Seven specimens from Station 57. Off Wata Mooli, 54-59 

 fathoms; all mud. 



It is with no little hesitation that I establish a new species of 

 Amphipholis c\osQ\y allied to the common European and American 

 species, and I have only done so after a careful comparison of a 

 large series of specimens from Norway, Denmark, England and 

 Naples, Algeria, Maine, Newport (Pt.I.), Cape Frio (Brazil), and 

 Talcahuano (Chili), with these seven from Australia. I fail to 

 find any constant character by which the specimens from Europe 



1^ Australia + ana, implying association. 



