117 



the distal wall by their proximal, sometimes almost tap-like, proximal end, and 

 by means of a uniporous rosette-plate are connected with the proximal zooecium, 

 whilst their more arched basal surface is grown together with the frontal mem- 

 brane of the distal zooecium. Seen from the frontal surface they are egg-shaped, 

 seen from the side triangularly rounded, and their subopercular pertion, which 

 is turned in towards the distal zooecium, forms an obtuse angle with the semi- 

 circular, outwards facing mandible which has a chitinous margin, but no »lucida«. 



The ocecia are large, broads flatly arched, rugged, and furnished with a pro- 

 truding proximal rim, which is separated from the other part by a ring-shaped 

 impression. From each of the distal zooecium's calcified lateral margins issues a 

 narrow, obliquely triangular calcareous plate, which pushes in between the endo- 

 ooecium and the ectoooecium, and comes to lie over the former with its 

 concave lower surface. It is furnished with a shorter inner; and a longer outer, 

 free marginal edge. 



The colony is bifurcated up to three times and the zooecia arranged in four 

 longitudinal rows. 



A single colony of this species was taken by the Ingolf Expedition at lat. 

 60" 17' N. long, 54" 05' W., at a depth of 1715 fathoms. 



All the Farciminaria species which Busk has described in the Challenger 

 Report except F. atltintica undoubtedly belong to this genus. 



Farciminaria Busk p. p. 

 The zooecia have a larger or smaller number of small, spine-like processes, 

 which are placed either on the frontal membrane or on the lateral margins; the 

 ocecia are surrounded by kenozooecia; an avicularium similar to that found in 

 Columnaria occurs in a few cases; the colony not jointed. 



F. uncinata Hincks. 

 Annals Nat. Hist. ser. 5, Vol. XIV. 1884, pag. 277, PI. VIII, fig. 2. 



(PI. I, figs. 10 a— 10 d). 

 The zooecia, the whole frontal surface of which is membranous, evenly in- 

 crease in breadth towards the broadedly rounded distal end, which is sometimes 

 furnished with two short spine-like processes. The frontal surface a little proxi- 

 mally to the operculum has on either side a denticle similar to these, and a 

 similar denticle, which varies somewhat in size and is sometimes double, arises 

 from each lateral margin a little distally to the proximal end of the zooecium. 

 It points in towards the middle line of the zooecium, and seems to be placed 

 under the frontal membrane. The triangular distal wall has within its basal rim 



