General History of the Marine Polyzoa. 179 



form near the top of each zooeciura, placed one on each side 

 and pointing downwards. There are no traces of anything 

 more. The appendages of tlie Farcimia are remarkable for 

 their size and are of a peculiar type. 



In my previous description of this species I have referred 

 to a structural similarity between its avicularia and those of 

 ScrupoceUaria ; but more accurate observation has convinced 

 me that there are most important differences between them. 

 They consist of an elongate avicularian chamber, tapering 

 slightly downward, convex in front, and adnate to the side of 

 the cell a little below the oral extremity. The top (which is 

 flattened) is occupied by the mandibular apparatus and carried 

 out in front into a small beak-like process; the mandible is 

 rounded. A raised calcareous margin surrounds the chamber 

 (which is also calcareous), and the front is closed in by a 

 chitinous covering. As I have mentioned, the space between 

 the rows of cells is almost entirely occupied by the avicularian 

 appendages. 



The differences between Farcimia appendiculata and 

 Memb. articulata as figured by Mr. Waters, which I have 

 just described, can hardly be due to the changes which have 

 taken place in the fossil. Traces of the large avicularian 

 chamber, which is formed of calcareous material, must have 

 survived, for this structure in the recent form, with the excep- 

 tion of its chitinous envelope, was not materially affected by 

 incineration. 



The ooecium in F. appendiculata is immersed, as it is in 

 many of the Flustrce. In ovicelligerous cells the margin is 

 not carried round the top, its place being taken by the oral 

 arch of the ooecium ; the latter occupies a small intercellular 

 space. The ooecium is somewhat shallow, subglobular, the 

 front occupied wholly by a large circular orifice facing the 

 interior of the cell and probably closed by a membrane. 

 Above the operculum of the cell, immediately under the oral 

 arch of the ooecium, is a narrow slit-like opening through 

 which the embryos escape. 



In a previous description of this species* I have referred to 

 certain remarkable appendages which are distributed in large 

 numbers over the zoarium. These consist of tall, erect, strap- 

 like bodies, formed of shining membrane of a light brown 

 colour, broad below and for a great part of their length, but 

 tapering off abruptly within a short distance of the tip and 

 terminating in a sharp point. They seem to be always 

 connected in some way with the avicularium — sometimes 



* Ann. & Mag. Nat. Hist, for March 1883. 



