247 



has an ascending distal margin, is high, trapeziformly pointed and provided with 

 a rounded triangular opening on the frontal surface in its proximal part. A 

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

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

 proximal side of the above mentioned, vertically protruding avicularium there 

 is a narrow, almost slit-like cavity, the adzooecial, infra-scapular chamber of the 

 mother-zooecium, and in the bizocecial internode only the pedal chamber on the 

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



The ooecium. The gonozocecium is a mother-zooBcium, and its sternal area 

 has 3 fenestrse and 3 spines, which fill the broad but low frontal sinus. The 

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

 frontal wall, are provided 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 partially. An avi- 

 cularium is wanting on the abzocecial as well as on the adzooecial side of the 

 gonozocecium. On the latter side we find two widely separated lateral chambers, 

 a rudimentary scapular 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 ooecium is covered by the distal zocecium, the small 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, bipartite fenestra, which is bounded proximally by the distal, curved 

 mai-gin of the aperture and distally by two curved lines that join centrally in a 

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

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

 ing, raised reticulation of which ends in a number of tubercles and spinous pro- 

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

 the ooecium covered by the zooecium is provided with numerous, scattered, cyl- 

 indrical spinous processes. 



Form of colony, hi this species two bizocecial internodes generally succeed 

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



I have examined a number of colonies from Port Phillip. 



