THE MOUNT DESERT REGION" 



313 



Cauloramphus Norman, 1903 



Cauloramphus cymbaeformis (Hincks), 1887. (Osburn, 

 1912, p. 230 (Memhranipora), synonymy; Whiteaves, 1901, 

 p. 96 {Memhranipora), Gulf of St. Lawrence.) Very common 

 on stems of hydroids and other bryozoans, rarely on algae, 

 shells and pebbles. Taken in thirty dredging stations, but in 

 none of the shore stations. Its known range is from south 

 of Cape Cod to Arctic America, Greenland, Spitzbergen, and 

 the Kara Sea. 



The zooecia are very deep in comparison with their length, 

 and they are especially characterized by the presence of tall 

 stalked avicularia among the spines. These avicularia appear 

 to begin their development like the spines, then enlarge gradu- 

 ally upward and terminate in a clavate portion with a small, 

 pointed avicularium. There are no ovicells. This species is 

 also peculiar in its manner of growth, as in hundreds of 

 colonies which I have seen nearly all were attached to the 

 stems of Bryozoa and hydroids. The dorsal surface of Den- 

 drobaenia murryana is a favorite situation. 



Amphiblestrum Gray, 1848 



Amphiblestrum flemingii (Busk), 1854. PL 6, figs. 8-9. 

 (Osburn, 1912, p. 231 {Memhranipora) for references.) Not 

 uncommon on stones and shells and taken at thirteen dredging 

 stations; rare, and occurring at only two shore stations. It 

 is found from the Mediterranean Sea to Spitzbergen in Euro- 

 pean waters. On the North American shore it appears to be 

 common from Cape Cod to Nova Scotia, and it has been re- 

 corded several times from Greenland, but strange to say it 

 has not been noted in collections from eastern or northern 

 Canada, where it seems to be replaced by the following species. 



The frontal area is partially closed in by a calcareous layer 

 (cryptocyst), leaving a somewhat trilobate membranous 

 space. Four to six spines is the usual complement, one of 

 these usually attaining a much larger size than the others. 

 Occasionally all the spines are wanting. The ovicell is 

 rounded, with a raised rib, which usuallv encloses a somewhat 



