Art. XIY. — Descriptions of Few, or Little Knoivn, 

 Polyzoa. 



Part VIII. 



By P. H. MacGilliyray, M.E.C.S, F.L.S. 



[Read 20th November, 1884.] 



Family Catenicellid^:. 



Catenicella gracilenta, n. sp. Plate I, fig. 3. 



Cells much elongated, very narrow ; mouth arched above, 

 slightly hollowed below, or subcircular. Anterior surface 

 papillose ; posterior, smooth. A narrow, entirely lateral 

 vitta extending the whole length of the cell. Lateral 

 processes small, usually with a sharp angle above projecting 

 outwards and forwards ; a minute avicularium opening out- 

 wards on the outer edge. Ovicell cemented to the front of 

 the cell above, which is sessile on the ovicelligerous cell, with 

 a quadrate smooth area. 



Port Phillip Heads, dredged by Mr. J. B. Wilson and 

 myself. 



This is a small species, readily distinguished by its 

 exceedingly slender cells. The ovicell is peculiar. As in 

 C. elegans, Buskii, fusca, and some others, it is cemented to 

 the front of the cell above, which is sessile on the ovicelli- 

 gerous cell. On the front of the ovicell is a quadrate, 

 smooth area, about twice as high as broad, totally different 

 from the marking of any other species. I had, unfortunately, 

 not seen the ovicell before the plate was lithographed, so 

 that it is not figured. The specific name was suggested by 

 Mr. Wilson. 



We have several other forms of Catenicella, which I believe 

 to be different from those described. The discrimination 

 of the minute species is not always easy, and the whole 

 genus requires a careful revision, which I hope to be soon 

 able to make. 



