762 " THETIS " SCIENTIFIC RESULTS. 



ZYGOMETRA ELEGANS {Bell). 



Antedonelegavs, 1884, Bell, Rep. Zool. Coll. H.M.S. "Alert," p. 



162, pi. xiii., figs. B, Ba (Port Molle ; Thursday Island). 

 Aiitedon fiucttia'ns, 1888, P. H. Carpenter, " Challenger" Reports, 



Zool., vol. 26, p. 94, pi. viii. (8° 56' S. lat., 136° 05 ' E. 



LONG.). —1898, Doderlein, Denkschr. Ge.s. Jena, vol. viii., 



p. 475, pi. xxxvi., fig. 1 {Thursday Island). 

 Zygometro, elegans, 1909, A. H. Clark, Zool. Anzeiger, vol. 34, 



p. 367 [Mermaid Strait, N. W. Australia). 

 Di^erential CJiaraclers. — In Zygometra elegans the II Br series 

 are 4 (3 + 4), but the .succeeding division series aie entirely or 

 mostly 2 ; the occurrence of the III Br series is not confined to 

 the inner branch from the II Br series"^. 



Specimens in the Australian Aluseum Collection. — Mast Head 

 Island — One specimen with about .sixty arms each about 70 mm, 

 long; slightly more division series of 4 (3 + 4) are present than 

 usual. Lagoon, Mast Head Island — One specimen with forty 

 arms ; the single remaiuing entire cirrus has fifty-six segments. 

 Port Denison — Two specimens ; one is a fine example with sixty 

 arms about 100 mm. long and cirri xix., 45-48, 35-40 mm. long ; 

 the II Br series are 4 (3 -1- 4), the remaining series 2 rarely, on the 

 exterior of the rays, 4 (3 + 4); this specimen agrees with four 

 others at hand from Mermaid Stiait, North-western Australia, 

 collected by the German ship "Gazelle"; the other specimen is 

 considerably smaller with twenty-nine arms 65 mm. long, the 

 II Br series being 4(3 + 4) and the III Br series 2 ; the cirri are 

 XX., 35-39. Port Molle — One small specimen with eighteen arms 

 about 50 mm. long and cirri xviii., 22-24, together with aim 

 fragments from a larger individual. Port Curtis — Three speci- 

 mens ; one has the centiodorsal large, thick-discoidal, with the 



3 In working over the magnificent collection of Comatulids made at 

 Singapore by Mr. Svend Gad, I found that the common Zygometra occurring 

 there and in the Mergui Archipelago is not the same as that called elegans 

 by Bell though it had been united with that species by Carpenter. It is a 

 twenty to thirty armed form, and the III Br series, which are always 2, 

 are only developed interiorly in 1, 2, 2, 1 order. I thought at the time 

 that the name Jinctuans covered this species, but I now find that fluctuans 

 is in reality only small elegans, and that the name is not available for the 

 Singapore species at all. I therefore propose that it be called Zygometra 

 comotto, sp.nov., reinstating a nome?i?n«(i?tm long ago applied to it in MS. by 

 Carpenter. A satisfactory description of Zygometra comata will be found 

 in Vidensk. Medd. fra den Naturhist. Forening i Kobenhavn, 1909, p. 151 

 (" Zygometra Jliictuans") ; it occurs in the Mergui Archipelago, atSingapore, 

 and among the Philippine Islands. 



Small specimens of this species are readily distinguished from small 

 specimens of Z. elegans by the regularity in the development of the III Br 

 series, these in comata appearing only internally, two to each ray. 



