780 " THETIS " SCIENTIFIC RESULTS. 



twenty to forty subequal segments, and perfectly smooth dorsally. 

 The ambulacra are without ambulacral plating. The centrodorsal 

 is discoidal, thick and broad. The pinnules are long and 

 moderately stout in the earlier part of the arm, where they tend 

 to be prismatic, but become shorter and more slender distally ; 

 the proximal pinnules are not essentially different from those 

 following. 



Range. — Carribean Sea to southern Brazil ; St. Helena ; West 

 Africa ; Cape Colony to Suez, and eastward to Australia, the 

 South Sea Islands, and southern Japan. 



TROPIOMETRA AFRA {Hartlaub). 



ui.nledo7i afra, 1890, Hartlaub, Nachr. Ges. Gottingen, Mai, 1890, 



p. 172 (Bowen). 

 Tropiomelra afra, 1908, A. H. Clark, Proc. U.S. Nat. Mus., vol, 



36, p. 315 [Alisaki, Japan; South Pacific). — 1909, A. H. 



Clark, Vidensk. Medd. fraden Naturhist. Foreuing i Koben- 



havn, 1909, p. 184 (Sowen ; Korean Straits). 

 Differeyitial Characters. — This is a large and stout species with 

 arms usually somewhat over 200 mm. long, which are rounded 

 and perfectly smooth dorsally, and stout cirri with usually from 

 30-35 or more segments. So far as known the colour is always 

 either entirely yellow or entirely violet, never mottled. 



Australian Records. — Bowen ; I have also examined a specimen 

 labeled " South Pacific " which probably came from Australia. 

 •Only three Australian specimens are known, two having come 

 from Bowen. 



Distribution. — From Queensland this species ranges northward 

 to southern Japan where it is common in the Korean Straits and 

 abundant at Misaki. 



TROPIOMETRA ENCRINUS, A. H. Clark. 



Tropiometra encrinus, 1911, A. H. Clark, Proc. U.S. Nat. Mus., 

 vol. 40, p. 36 (East Indies). 



Differential Characters. — This is a smaller form than the pre- 

 -ceding, the arms being rarely more than 120 mm. in length ; each 

 brachial after those just at the base of the arms bears a pronounced 

 median tubercle or keel in its distal portion ; the cirri have 

 between twenty and twenty-five segments. The colour is mottled 

 yellow and purple. 



Australian Records. — There are no definite Australian records, 

 but I have examined a number of specimes labeled " South 

 Pacific " which possibly came from there. The species occurs at 

 i^orfolk Island, and apparently in the Marshall Group. 



