7 



3. Acanella sp. ? 



Stat. 45. 7 24/S., ii8i5'.2E. 794 meters. Fine grey mud. 



The specimen consists of a fragment comprising three calcareous internodes joined at 

 their bottom to a horny internode which supports the three. The longest of these internodes is 

 1.8 cm. long, and the others are nearly as long. Diameter 1.2 mm. The surface is longitudinally 

 grooved or fluted. 



This specimen may possibly be Acanella chilensis T which has the branches arranged in 

 irregular whorls of two or three. 



M o p s e i n ae. (See definition on page 4). 

 MopSCa Lamouroux. 



Mopsea Lamouroux. Histoire des Polypiers coralligenes flexibles, 1816, p. 465. 



Mopsea (in part) Ehrenberg. Corallenthiere des Rothen Meeres, 1834, p. 131. 



Mopsea Gray. Proceedings Zoological Society of London, 1857, p. 283. 



Mopsea Milne Edwards et Haime. Histoire naturelle des Coralliaires, Vol. I, 1857, p. 197. 



Mopsea (in part) Dana. Synopsis of the Report on Zoophytes, Wilkes Expedition, 1859, p. 144. 



Mopsea Studer. Monatsbericht der Konigl. Akademie der Wissenschaften zu Berlin, 1878, p. 665. 



Mopsea Studer. Versuch eines Systemes der Alcyonaria, 1887, p. 46. 



Mopsea Wright and Studer. Challenger Reports, the Alcyonaria, 1889, pp. XLV, 40. 



The original definition for this genus (LAMOUROUX 1816) is as follows: 



"Polypier dendroide a rameaux pinnes: ecorce mince, adherente, couverte de mamelons 

 tres petits, elonges, recourbes du cote de la tige, epars ou subverticelles". 



Subsequent writers modified this definition so as to admit certain species of Melithteidte , 

 until STUDER (1887) defined it as follows: 



"Colonie in einer Ebene verzweigt, Polypen klein, keulenformig, in dichten Spiralen 

 ringsum den Stamm angeordnet. Kelchschuppen klein, niedrig und stachlig". 



WRIGHT and STUDER (1889) expanded this definition to considerable length on page 40, 

 but give a much shorter definition on page XLV which is practically the same as the one by 

 STUDER, quoted above. 



"The colony is branched and expanded fan-like in one plane. The polyps are small, 

 club-like in form, and arranged in dense spirals around the stem. The calyx scales are small, 

 short and spiny". 



The above definition is the one adopted in this work. 



The type species of this genus is Mopsea encrinula (Lamarck). Other known species 

 are M. dichotoma (Linn.), and the two new species about to be described. 



i. Mopsea flava new species. (Plate IV, figs, i, \a\ Plate V, fig. 5). 



Staf. 117. io'.5 N., 122 56' E. 80 meters. Sand and coral. 

 Colony strictly flabellate in form, 26 cm. in height, and 17 cm. broad. 3.6 cm. above 



1 Challenger Report, the Alcyonaria, 1889, p. 31. 



SIBOOA-EXPED1TIE XIII 0*. 



