352 MB. G. BUSK ON THE SPECIES OE CELLEBOBA 



Orifice subarcuate, with a wide notch.. Preoral rostrum very 

 variable in size and conformation ; small and conical, or very 

 large and cylindrical towards the end, and deeply channelled on 

 the posterior aspect, but always hollow ; supporting near the 

 extremity a small avicularium with a semicircular mandible; 

 numerous, very large, interspersed avicularia, with a duckbill- 

 shaped mandible, shutting down into a deeply cupped beak, the 

 end of which is gouge-shaped and the border entire and sharp. 



Hob. St. 149 d. Eoyal Sound, Kerguelen, 20-60 fms. St. 

 149 i. Off Christmas Harbour, 45-120 fms. St. 303. Lat. 45° 

 31' S., long. 78° 9' W. ; 1325 fms., Glohigerina-ooze. St. 315. 

 Lat. 51° 40' S., long. 57° 50' W.; 5-12 fms., sand. 



Though exhibiting great diversity, especially in the greater or 

 less development of the rostrum, the specimens from the above 

 localities agree in all essential particulars, such as the shape of 

 the orifice and oral valve, the presence of the small rostral semi- 

 circular avicularium, which is sometimes terminal, sometimes 

 seated below the summit, which may be prolonged into an acumi- 

 nate point beyond it ; but more particularly the peculiar con- 

 formation of the numerous and large interspersed avicularia. 



At first I had divided the form into three species (0. Eatonensis, 

 G. magellensis, and C. rostrata), but am now quite satisfied that 

 they are all specifically identical. 



17. C. ovalis, n. sp.* 



Char. Zoarium ramose, branches cylindrical, tapering. Zooecia 

 distinct, very prominent in the younger parts. Orifice orbicular, 

 with a notch on one side. Preoral process strong, hollow, pointed, 

 varying very much in height, and being much more prominent 

 and pointed on the younger branches than on the main stem; it 

 supports an avicularium with a wide triangular mandible ; the 

 beak simple. Ooecia subrecumbent, with two or three raised pores 

 in front. Interspersed avicularia few, of an oval form. 



Hob. St. 75. Lat. 38° 37' N., long. 28° 30' "W. ; 450 fms., sand. 



Parasitic on a bundle of radical fibres of a Sertularian. 



The labial notch in this case resembles that which occurs in 

 most of the Eetepores ; it is not median, but placed to one side, 

 and appears, as in Eetepores, to have a tendency to become con- 

 verted into a suboral pore. 



* "Chall. Rep." pi. xxviii. fig. 5. C. ovalis really belongs to the Holo- 

 stomatous division. 



