258 



pore surrounded by a ring which is continuous with the longitudinal ridge. The 

 aperture is provided with well-developed, distinct hinge-teeth and has a proximal 

 concave margin. 



Strophipora Harveyi Wyv. Thompson. 

 Catenicella Harveyi Wyv. Thompson, Natural History Review, V, 1858, p. 137. 

 — — Wyv. Thompson, Proced. Dublin Univ. Zool. and Botan. 



Associat. I, p. 81, PI. VII, figs. 1, 2. 

 Strophipora Harveyi Mac Gillivray, Transact. R. Society of Victoria, 1895, 



Vol. IV, p. 17, PI. II, figs. 9—12. 

 (PI. XXl, figs. 6 -6 f). 

 The zooecia are of an oblong, quadrangularly oval form, and the frontal sur- 

 face, which is less strongly arched than the basal surface, is most strongly arched 

 immediately on the proximal side of the aperture, from which it descends to- 

 wards the proximal end. 



The lateral chambers. The scapular chamber is everywhere, except on the 

 adzocecial side of the mother-zooecium, developed as an avicularium of medium 

 size at least, which is always directed so much towards the frontal surface that 

 the surface of the mandible can be seen, when the zooecium is regarded from 

 this side, and it may sometimes be altogether fronlal. It has generally a some- 

 what ascending roof and may vary considerably in size, and in the single zooecia 

 at least a somewhat curved, rib-like thickening springs from its proximal end. 

 The supra-scapular chamber is a large, more or less ascending, membranous, 

 pointed cavity, while each half of the frontal surface is occupied by a large 

 infra-scapular chamber, which communicates with the zooecium through a longi- 

 tudinal row of 4 — 5 very scattered rosette-plates. The two chambers are separated 

 by a longitudinally furrowed, narrow median ridge, and each of them is sepa- 

 rated from the adjoining pedal chamber by a similar lateral ridge. Each of them 

 is generally separated from the supra-scapular chamber by two low ridges, the 

 starting point of which is on a level with the transverse ridge of the avicularium 

 and which pass, one to the margin of the aperture, the other to the lateral ridge. 

 The membranous wall of the infra-scapular chamber runs out on each side into 

 two conical expansions, which are situated close to the aperture, and a couple 

 of similar expansions may also appear in the distal part of the basal surface. 

 The two pedal chambers occupy the entire basal surface of the zooecium and are 

 likewise separated by a longitudinally furrowed median ridge, while again each 

 chamber is divided into two unequally large parts by an extremely narrow, low, 

 compressed, longitudinal ridge, which appears in its outer half and serves to 



