THE MOUNT DESERT EEGION 311 



pairs being- larger and bent somewhat forward; the others 

 are directed upward and curve somewhat over the aperture. 

 The avicularium is smaller in comparison with the zooecia 

 than in the preceding species. The ooecium has a transverse 

 rib across its middle. Seen from the dorsal side, the zooecium 

 has two pairs of lateral pore chambers and a single large 

 anterior one, with spinules projecting into the chambers. 



Callopora dumerilii (Audouin), 1826. PI. 6, fig. 6. (Whit- 

 eaves, 1901, p. 96 (Memhranipora), Gulf of St. Lawrence.) 

 Distributed on both sides of the North Atlantic, in Europe 

 from Norway to the IMediterranean. Recorded only once pre- 

 viously from North America, by Whiteaves (I.e.) on the au- 

 thority of Norman. The species was taken at dredging sta- 

 tion 13, on Googins Ledge, in the inner bay, August 31, 1927, 

 on the bark of a water-logged branch. In the writer's collec- 

 tion there are also specimens from Georges Bank. 



Zooecia regularly arranged, well separated by deep fissures, 

 the walls rather high and thin-edged; a pair of elongated 

 spines, one on either side at the level of the operculum ; some- 

 times an additional pair of smaller ones. The membranous 

 area of the front is quite regularly oval on its larger proximal 

 part, then suddenly narrowed forward at about the level of 

 the operculum. Ooecium more or less globose, sometimes 

 considerably elongated, in other cases shorter than wide, even 

 in the same colony. Avicularia are wanting on the Mt. Desert 

 Island specimen, but pointed avicularia are common to the 

 species ; in the few American specimens I have seen they are 

 not as numerous as in European material. 



Tegella Levinsen, 1909 



Tegella arctica (d'Orbigny), 1851. PI. 6, fig. 5. (Osburn, 

 1912, p. 229 {Memhranipora) ; Whiteaves, 1901, p. 96 {Mem- 

 hranipora sophiae.) Eare, taken only at shore station 11 

 and dredging stations 75, 102, and 119. A northern species 

 of wide range, occurring on the American coast from Green- 

 land to Cape Cod as well as the northern shores of Europe. 



