ITS SPECIES AND OVICELLS. 131 



TuBUCELLARiA FUSiFORMis, d'OrUgni). (Plate 15. figs. 1, 2, 3, 14.) 



Tuhucellaria fusiformis, d'Orb. Pal^ont. Fran9. vol. v. p. 337. 



Zoarium about 1 mm. in diameter, and at the end of each branch three 

 fresh branches are given off attached by two or three corneous tubes. 

 Occasionally there are also branches growing from the side of a branch. 

 The divisional lines of the zooecia can only be distinguished with difficulty 

 even when the outer membrane is removed by eau de Javelle, or by other 

 methods. 



The zooecia end in long peristomes, round the base of which there is a 

 divisional line, and the surface of the peristome is ribbed, having one or two 

 rows of pores between the ribs. The surface of the zooecia is pitted all 

 over and the peristomial pore is in a slightly projecting tube. 



This form corresponds more nearly with Pallas's description of Cellularia 

 opuntioides than any of the species recently thought to be opuntioides. 



The specimen from Torres Straits to which Busk referred as T. fusiformis, 

 d'Orb., in his ' Challenger^ Report, p. 100, is a much stouter species with 

 larger pores. To this I allude on p. 130. Harmer says that there is a Tuhu- 

 cellaria found by the ' Siboga ' Expedition which is probably T. fusiformis, 

 d'Orb. When passing through Paris I took the opportunity of examining 

 d^Orbigny's specimen, which is only the basal portion of a lateral branch, 

 and is only about the length of two zooecia; an examination of this fragment, 

 however, leaves me in no doubt as to the correctness of my determination. 

 D'Orbigny described it as having " cellules sur quatre faces oppos^es"; which 

 is correct for the basal zooecia of the branches of T. fusiformis, but in the rest 

 of the zoarium there are s.'x zooecia to a complete series. 



Loc. Straits of Malacca [d'Orh.), There is a specimen unnamed in 

 the British Museum (82.10.1.5.5.10) from Marie Louise, Amirante Is., Indian 

 Ocean, 17 fath., collected by the ' Alert.' Chuaka, Zanzibar, 3 fath. (518) ; 

 Wasin, Brit. East Africa, 10 fath. (520), collected by Crossland. 



TuBUCELLARiA ZANZiBARiENSis, sp. nov. (Plate 15. figs. 4-7.) 

 Zoarium delicate, about 0'5-0*8 mm. diameter. It cannot be said that 

 there are divisional lines, though the boundary of the zooecia can often be 

 traced in suitable preparations, and in the same way there is usually no line 

 separating the peristome. There is a distinct suboral pore in a slightly 

 raised tube, and the surface of the zooecium is covered with elongated pits. 

 The operculum is straight below, with a double chitinous wall on the distal 

 border, covering a third of the operculum. There are 22-24 tentacles. 



In a few nodes the peristomial ovicell is seen on most of the zooecia ; the 

 ovicells are curved below, but with the terminal tubular portion straight, and 

 the opening circular and as wide as the zooecium ; differing in these respects 

 entirely from the peristomial ovicells of T. cereoides and T. hirsuta, Lamx, 



