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margin and on either side of this a robust, conical, obliquely ascending spine. 

 The sternal area is provided with 5 small fenestrse, and each of the lateral sur- 

 faces of the gonozocecium with a pear-shaped oval, most probably pedal, lateral 

 chamber. The frontal sui-face of the covering kenozooecium has 4 — 10 larger or 

 smaller fenestrse of very variable form. When occurring in small numbers several 

 of these fenestrse are very large and show by their lobate form, that they have 

 arisen by coalescence of several smaller ones. We may distinguish between an 

 outer, arch-shaped group and a group on the distal side of the aperture. All 

 four lateral chambers are developed, and the scapular one, appears as a small 

 avicularium, while the two supra-scapular chambers have coalesced into one, 

 which takes up the entire breadth of tlie kenozooecium (fig. 7 a), and which has 

 on either side a vertical, pointed, calcified outer wall. This chamber has besides 

 a group of rosette-plates in the roof of each avicularium, a great many scattered 

 plates in the median part, which is separated by a low ridge from the frontal 

 as well as from the dorsal surface of the kenozooecium. On the outer and the 

 basal side of the avicularium there is a small, oval, infra-scapular chamber and 

 separated from it a large, trapeziform pedal chamber. 



Form of colony. Apart from the fact that rows of 1 — 5 single zooecia, (which 

 may arise from both a mother- and a daughter-zooecium), may appear as ter- 

 minal branches, the alternation of uni- and bi-zocecial internodes is otherwise 

 regular, and two bizooecial internodes nowhere succeed each other. 



Of this species I have been able to examine some fragments from Port Wes- 

 tern, Victoria (Miss Jelly). 



Scuticella margaritacea Busk. 

 Catenicella margaritacea Busk, Voyage of Rattlesnake, I, pag. 356, Catalogue of 

 Marine Polyzoa, Cheilostomata, pag. 9, PI. VI, figs. 1, 2, 3. 

 (PL XX, fig. 3 a, PI. XI, figs. 5 a-5 c). 

 The zotecia rhombic-oval with an aperture, the proximal, more or less con- 

 cave margin of which is provided centrally with a small, well defined, sometimes 

 however quite rudimentary sinus, the entrance of which is bounded by two ex- 

 tremely short spines directed somewhat distally and pointed at the end. These 

 spines are sometimes widely separated, and the sinus then reaches its maximum 

 (colonies from the Bass' Strait), sometimes almost concurrent at the ends and 

 the sinus is then rudimentary or reduced to a pore (Port Phillip Heads). The 

 operculum, which does not entirely fill the aperture, has a proximal, concave 

 margin, and the sternal area is provided with five fenestrse disposed in an arch 

 or angularly. The cryptocyst lamina is of a broad, rounded triangular form, and 



