10 W. G. RIDEWOOD. 



Described by Harmer in Report of ' Siboga ' Expedition (10). Tubarium* Colony 

 very small and delicate ; almost colourless tubes, of prostrate habit, supported l)y 

 foreign object (calcareous branches of the Polyzoon Tuhucellaria). Extremities of 

 the branches with long spines borne upon the margins of the funnel-shaped ostia, 

 which measure "8 to 1 mm. across. AVidth of branches 1 to 1"5 mm. (text-fig. 5). 

 Polypides. All known individuals are female. Front of liuccal shield to end of 

 visceral mass '87 to 1*2 mm. Plumes five pairs, small end bulbs with refractive 

 l)eads present in first pair of arms of the bud, and occasionally on second and 

 third pairs also ; they may persist in the adult (10, p. 20). Stolon thin, much 

 longer than the rest of the polypide, usually directed away from the mouth, and 

 producing buds in great profusion. Free ova • 3 to '4 mm. across. 



Species sihogae. Material. One specimen, obtained at Station 204 of the 

 ' Siboga ' Expedition, at the Northern entrance of Buton Strait, off S.E. point of 

 Celebes^ in 75 to 94 metres. Bottom sand with dead shells. Described by 

 Harmer in Report of the ' Sil)oga' Expedition (10). Tuharium with a dense basal 

 encrusting portion, growing on a small rock, with stiff, erect and slightly branched 

 tubes, with numerous foreign inclusions in the substance of the test. Ostia 

 funnel-shaped, more or less alternate on two opposite sides of the branch, • 6 mm. 

 across, produced into a few peristomial spines, stifier and shorter than those of 

 C. gracilis. Width of branch 1 to 2 mm. (text-fig. 2). Polyjndes deeply pig- 

 mented ; all known individuals are male or neuter. Neuters with elongated trunk 

 region, with excessively long and slender stolon arising from near its a1)oral end, 

 and producing buds in great profusion ; gonads vestigial in buds, usually absent 

 in adults, but occasionally developed into functional testes (10, p. 84, and legend 

 to fig. 98). Plumes four pairs, without end ])ulbs and refractive beads. Front of 

 buccal shield to end of visceral mass "95 mm. Males with conical body, which 

 passes continuously into the stalk ; alimentary canal vestigial ; testes occupying 

 most of the trunk and part of the stalk. Plumes one pair, without pinnules, 

 surface with crowded refractive beads, at least in young males. Free ova not 

 known. 



Sub-genus Idiothecia. Cavity of the tuljarium multiple ; each ostium leading 

 into an unbranched, tubular cavity occupied by one polypide and its buds, and having 

 no connection with the other cavities of the tubarium. 



Species nigrescens. Material. Several specimens, obtained by the 

 'Discovery' in 1902 off Coulman Island, near Victoria Land, in the Antarctic 

 Ocean, in 100 fatlioms. Described by Lankester in Proc. Roy. Soc. (15). 



* In drawing up this table the distinctive features of C. gracilis, C. sihogae and C. levinseni have been 

 culled fi'om Harmer's monogi-aph ; an independent examination of his specimens was not made. It is to be noted 

 that Harmer's orientation of the polypide is not accepted ; the surface of the body which he terms anterior is 

 here spoken of as ventral. ' 



