BUGULA TURBINATA. 77 



habit, of an orange-brown colour when recent, but much 

 paler when dried. The cells are somewhat elevated at the 

 upper extremity ; and each of them slightly overlaps the 

 one above it. The number of spines is universally, so far 

 as I have seen, three : two are placed on the outer side of 

 the cell one of them on the upper angle of the aperture, 

 and the second behind it ; the third rises from the inner 

 and upper angle. The avicularium is the striking feature 

 of the species. It is of very large size, elongated, with a 

 much produced beak, which is slightly and gradually (not 

 abruptly) curved ; the head, as seen from above, has the 

 appearance of being compressed laterally, and altogether 

 wants the full rounded contour which we find in the 

 avicularium of the next species. The ovicells are pro- 

 duced in immense numbers; they are very prominent, 

 owing to the elevation of the cell at the upper extremity, 

 and, as seen in profile, have a very hood-like appearance. 

 The aperture is contracted. The branches are numerous, 

 and set closely together, and wind round the stem in 

 corkscrew fashion. They divide dichotomously a little 

 above the base into two principal segments ; and these 

 divide and subdivide, the whole assuming a flabellate 

 character. 



BUGULA TURBINATA, Alder. 

 Plate X. flgs. 5-8. 



BIRD'S-HEAD CORALMH*, Ellu, CoralL pi. raviii. flgs. O, H. 



CELLULARI A AVICULARIA, Pall. Blench. 68 ? : Gosse, Devonsh. Coast, 195, 



pi. x. 

 BUGULA TURBIWATA, Alder, Quart. Journ. Micr. So. T. 174, pi. rvii. flgs. 1-4 : 



Hincks, Dev. A Oornw. Cat. 37 (sep.). 



Zoarium orange-coloured when living, forming an as- 



