432 A. W. WATEKS ON FOSSIL CHILOSTOMATOUS 



preserved. The surface is smooth, and on each side, a little lower 

 than the aperture, there is a small oval opening. The oral aperture 

 is rounded above, and on each side near the base there is a minute 

 denticle. 



In a recent specimen from Natal the lower cells are attached to 

 the ground by a bundle of tubular fibres, of which several are 

 attached to each globulus. The bundle is naturally thickest in the 

 lowest part. The lower cells have all well-marked avicularia, 

 usually one on each side, but no " spines " (of Busk) ; while in the 

 upper cells the avicularia are rarer, and a spine on each side is well 

 developed. In the upper cells, with two well- developed spines, I 

 do not find any avicularia. As I have elsewhere remarked, it is 

 very important that the globuli from various parts of a colony 

 should be compared. 



Loc. Living : Algoa Bay (Busk), Natal (A. W.). Fossil : Bird 

 Rock. 



11. Catenicella laevigata, sp. nov. Plate XII. fig. 1. 



This has very few characters on which to make a species, and in 

 its simplicity differs from most of the Catenicellce. The shape of 

 the globulus is cuneiform, surface coarsely punctate. The zooecia are 

 almost tubular, and are nearly parallel on each side of the axis. 

 The aperture is circular at the distal end with a rounded notch on 

 the proximal ; but whether this is an oral sinus or only simulates 

 one in the way mentioned on page 423, I am as yet unable to say. 

 Dorsal and anterior surface smooth. Oral aperture 0-04 millim. 

 wide. This will probably be the smallest aperture of any Chilo- 

 stomatous Bryozoon yet described. 



From Bird Eock. 



12. Catenicella longicollis, sp. nov. Plate XII. figs. 2, 3, 4. 



Globulus cuneate, surface smooth, with a large avicularium at 

 each upper corner ; opening of avicularium turned rather more to- 

 wards the dorsal surface than the ventral; mandibular opening narrow, 

 curved, with the mandible directed ivpwards. An oval vitta marked 

 with transverse lines, just below the aperture, also a very minute 

 vitta on each side near the base. Aperture nearly circular, with a 

 broad wide notch below. Dorsal surface smooth, rounded, raised 

 to the centre of the zocecium. The tubular connexion from one 

 globulus to another very long, in some cases about half as long as a 

 zoarium. Closely allied to G. geminata, Thorns. Oral aperture 0-06 

 millim. wide. 



Loc. Fossil : Bird Eock, Muddy Creek, and Waurn Ponds. 



13. Catenicella cerctjmcincta, sp. nov. 



Globulus ovate, with a row of large foramina round the margin of 

 the zocecium, and one pore below the aperture. Aperture large, 

 rounded above, widest at the proximal edge, which is straight. 

 Oral aperture 0-08 millim. wide and 0*08 millim. long. 



