247 



has an ascending distal margin, is liigii, Irapezifornily pointed and provided with 

 a rounded triangular opening on the Ironlal suil'ace in its proximal part. A 

 similar, though somewhat smaller opening is found on the inlra-scapular cham- 

 ber while the pedal chamber has a large, oval opening. Immediately to the 

 proximal side of the above mentioned, vertically protruding aviculariuni there 

 is a narrow, almost slit-like cavity, the adzoa'cial, infra-sca|)ular chamber of the 

 mother-zocEcium, and in the bizod'cial internode only the pedal chamber on the 

 adzoCEcial side of the daughter-zooecium is on the whole wanting. 



The ocecium. The gonozo(rcium is a mother-zo<rcium, and its sternal area 

 has 3 fenestra' aiul 3 spines, which iill the broad but low frontal sinus. The 

 two larger distal spines, which have an inner cavity and a mostly uncalcified 

 JVonlal wall, are proxidcd with a head-shaped, inwards and proximally bent 

 terminal part, which is generally separated from the frontal sinus by a narrow 

 fissure. The extremely small, unpaired spine is situated between the terminal 

 parts of the two larger ones and separate these wholly or only i)artially. An avi- 

 culariuni is wanting on the abzooecial as well as on the adzoa-cial side of the 

 gonozoa^cium. On the latter side we find two widely separated lateral chambers, 

 a rudimentary scaj)ular one and a larger pedal, while the scapular and the pedal 

 chambers on the former side are represented by an auriculate process with one 

 or two narrow pores. 



The broad oa'cium is covered by the distal zocecium, the snuiU sternal area 

 of which is provided with two extremely small fenestrse and two ribs or spines 

 which meet in a suture, while the covering part of its frontal surface has a large, 

 broad, l)i[)artite fenestra, which is bounded proximally by the distal, curved 

 margin of the aperture and dislally by two curved lines that join centrally in a 

 point directed towards the aperture. All the part of the ocecium to be seen through 

 this perforation is [irovided with numerous, closely situated pores, the separat- 

 ing, raised reticulation of whii'li ends in a number of tubercles and spinous pro- 

 cesses. With exception of the proximal margin the part of the frontal surface of 

 the ocEcium covered by the zoo'cium is provided with numerous, scattered, cyl- 

 indrical spinous [irocesses. 



Form of colony, ha this species two bizocx'cial internodes generally succeed 

 each other, the latter springing from a daughter-zooecium. 



I have examined a number of colonies from Port Phillip. 



