378 



Plate VI a. 



Fig. 1 a. Tluiltimoporella graiuilala n. sp. X 40. 



— 1 b. The s;iiiu- species, from the basal surface. 



X 23. 



— 1 e A gmio/.iKL'eiuiii nf the same species with a 



ileveliipiiiH ooccium. The gonozoCEcial oper- 

 culum is seen. X 40. 



— Id. An avicularian nianiliblc of the same spc- 



X :>:>) 



— 1 f. Spicula of the same species. X 200. 



— 2 a. Th(iltimoi>ortlla iininiiliita, var. tiihifeni n. 



Within the aperture both of the zocecia anil 

 of the avicularia, the remarkable continua- 

 tion of the polypide tube (t) with its frontal 

 aperture can be seen meetinj; the distal 

 wall. X 40. 



— 2 b. The same form from the basal surface. The 



continuation of the polypide tube (,t , which 

 sends a lateral branch to a rosette-plate in 

 two of the zooccia, is visible inside. This 

 continuation has a peculiar trapeziform shape 

 in the (<onozo<i'cium. X 23. 



— 2 c. A zocfcium of the same form, lateral view. 



It is seen, that the continuation of the poly- 

 pide tube meets the basal jnirt of the distal 

 wall. X 40 



— 2d. Two gonozocrcia of the same form with 



ooceia. X 40. 



Fig. 2 e. Spicula of the same form. X 200. 



— 3 a. TlmUimojmrdla novae hollandiav (Hasw.). 



X 40. 



— 3 b. The same species with a somewhat smaller 



avicularium. X 40, 



— 3 c. Two avicularian mandibles of the sajne spe- 



cies. X 40. 



— 3 d. The same species, from the basal surface. 



X 23. 



— 3 e. Another colony of the same species, from 



the ba.snl surface. X 23. 

 - 3 f . ,Si)icula of the same species. X 200. 



— 4 a. Tlmlamoi>orclht Jervoisi (Hincks). X 40. 



— 4 b. The same species from the basal surface. 



X 23. 



— 4 c. Operculum of the same species. X 40. 



— 4d. Spicula of the same species. X 200. 



— .'i a. Thalamoporella mamillaris (Lamx.l. X 40. 



— .">b, Five opesiuUe of different zon?cia, to show 



the variation in shape of the opesiular out- 

 growths and in the number and structure 

 of the protecting spinous processes. X 75. 



— .1 c. An avicularium of the same species. X 40. 

 ,') d. An avicularian mandible of the same spe- 

 cies. X 75. 



— 5 e. Spicula of the same species. X 200. 



