1908] Robertson. — Incrnsting Bryozoa. 297 



Zoariutn forming a delicate, branching' tracery ; branches aris- 

 ing from the snmmit or side of zoo^cia (pi. 21, fig. 59). ZooRcia 

 tnbnlar below, expanding above, elongated, ovate, more or less 

 distant, sometimes growing in close patches lying together ir- 

 regularly, sometimes quite remote from each other; finely 

 striated, subcarinate in front (fig. 60) ; orifice arched and raised 

 above with a sinus on the lower margin. Oacia, oc, small, glob- 

 ose, with a boss or umbo, um., in front, borne on a lateral zooecium 

 inferior in size to the ordinary ones. 



This species is probably abundant, but it is so inconspicuous 

 as to escape observation easily. It occurs at various localities 

 on our southern coast between tide marks. 



Escharidae (part) Smitt. 



Celleporidce (part) Johnston, 1847. 



Eschar idee (part) Smitt, 1867. 



MembrainporidcB (part) Busk, 1854. 



Escharidce, Hincks, 1880. « 



Zoariutn calcareous, incrusting, erect, and lamellate, or ra- 

 mose. ZooRcia without a membranous area or raised margins: 

 (a) with a simple primary aperture, horseshoe-shaped, semiellip- 

 tical, or suborbicular ; or (b) with an elevated secondary orifice 

 inclosing an avicularium ; or (c) with a primary orifice having 

 a dentate lower margin and a secondary orifice channelled in 

 front or entire; or (d) with the lower margin elevated into a 

 mucro ; in all cases destitute of a true sinus and special pores. 



As Hincks remarks, this is a somewhat miscellaneous group 

 of forms. They are, as a rule, characterized by the possession of 

 one or more denticles, or an avicularium inside the peristome. 

 This is not true of Lepralia, how^ever, which seems to be included 

 here because it does not fit anywhere else. The genus Lepralia 

 is not common in this fauna, there being but one species so far 

 known. 



KEY TO THE GENEEA OF ESCHAEIDiE. 



1. Those with simple orifice Lepralia 



1. Those with a secondary orifice 2 



2 Those in which the secondary orifice is channelled in front 3 



2. Those in which secondary orifice is not channelled in front 5 



