"endeavour" scientific results. 170 



Family PLUMULARIID^. 



Genus Nemertesia, Lamouroux. 



(Antennularia, Lamarck.) 



Nemertesia ciliata, sp. nov. 



(Plate xxxvi., fig. 1.) 



Hydrophyton about a fcot in height, in one plane, stem and 

 main branches polysiphonic, beset with very numerous small 

 monosiphonic branchlets, which are biserial, varying from 

 opposite to alternate, and are divided into distinct internodes, 

 each of which, except the proximal one, bears several whorls of 

 hydrocladia. Hydrocladia mostly in whorls of three or four, 

 alternating in position with those above and below, divided into 

 hydrothecate long internodes and intermediate short ones 

 bearing sarcothecae only. 



Hydrotheca? very small, cup-shaped, adnate up to the margiu, 

 which is smooth, 



Sarcotheca? large, wine-glass-shaped, bithalamic, canaliculate, 

 moveable ; one in front of each hydrotheca, two laterals above 

 it, one on each intermediate internode, and two in the axil of each 

 hydrocladium. 



Gonothecas borne on the bases of the hydrocladia, campanulate, 

 very thin and delicate. 



Colour. — Light brown. 



A very pretty species, the best specimen of which has a stem 

 over ten inches in height, with several large branches and 

 numerous smaller ones, all given off nearly in one plane, and at 

 about 45°. The branches extend downwards to within about an 

 inch of the base of the stem, and the ultimate branchlets, which * 

 are monosiphonic, are closely set, not being more than three to 

 six millimetres apart. They are indifferently opposite or alternate, 

 and are closely fringed throughout by the delicate hydrocladia, 

 which are like fine cilia, averaging only from two to three 

 millimetres in length. The internodes of the branchlets vary 

 much in length, supporting from one up to six or eight whorls 

 of hydi-ocladia. On some branchlets each whorl consists of three 

 hydrocladia, on others four, and the same branchlet may have 

 them in fours up to a certain point and in threes beyond it. 

 Besides this, other irregularities occur ; thus in many cases, 

 especially on the proximal parts of the branchlets, the hydro- 

 cladia which should constitute a whorl are set at unequal heights. 



Loc. — Oyster Bay, Tasmania, 60 fathoms. 



