N.B. The present Part contains about one-half of the Cheilo- 

 stomatous suborder, the remainder of which will be included in 

 a second. Owing to the rapid accumulation of materials during 

 the progress of the Work, it has not been possible to adhere to 

 any regular sequence in the Plates, and it has been found ne- 

 cessary to reserve one Plate (LXXIL), containing the figures of 

 Diachoris inermis, for the ensuing part of the Catalogue : for the 

 same reason also the figures of several species of Membranipora 

 and of a species of Vincularia, to be afterwards described, appear 

 in Plates LVIII., LXL, LXV. and LXVIII. G. B, 



