Zoology.-] NATURAL HISTORY OF VICTORIA. IPolyzoa. 



Plate 196, Fio. 1. 

 THAIROPORA ARMATA (McG.). 



[Genus TIIAIROPoRA (McG.)- (Sub-kingdom MoUusca. Class Polyzoa. Order 

 Infundibulata. Sub-order Cheilostomata. Family Microporidae.) 



Gere. Char. — Zooecia calcareous, traversed by bands or transverse fissures and covered 

 with a continuous epitheca ; mouth arched, higher than broad, lower margin of operculum 

 hollowed : a stout, unarticulated, mamillate or buUate process in a separate tract on each side of 

 the mouth. Avicularia at the base of or replacing zooecia, mandible strengthened by a stirrup- 

 shaped thickened chitinous band.] 



Description. — Zooecia quadrate, alternate, of a'whitish colour, calcareous layer 

 granular or perforate, with few indistinct lines; epitheca rather thin. Oral processes 

 large, of equal size. Avicularian mandibles broadly lanceolate, directed upwards, 

 strengthening band produced upwards from the junction of the lateral branches 

 and with a broad membranous band on either side. 



Reference. — P. H. MacGillivray, Trans. Roy. Soc. Vict., Dec, 1881. 

 Queenscliff. 



Explanation of Figure. 

 Plate 196. — Fig. I, group of zoreoia magnified, showing two avicularia. 



Plate 196, Fig. 2, 

 THAIROPORA MAMILLARIS (Lamx. sp.). 



Description. — Zooecia quadrate, alternate; calcareous lamina very thin, with 

 few lines ; epitheca thick, brown or purple. Mouth with the oral processes of 

 moderate size, equal or occasionally one larger. Avicularian mandibles elongated, 

 branches of strengthening band meeting at an acute angle and produced into a 

 vertical process, without membranous margins. 



Reference. — Prod. Zool. Vict., pi. 25, fig. 4. 



This species has ah-eady been described as Memhranvpora 

 mamillaris and figiu'ed on plate .25, but a fresh figure is now 

 given to better show the differences between it and T. armata, 

 from which it is readily distinguished by its purplish or dark 

 brown colour, the thicker epitheca, and especially by the different 

 form of the stirrup-shaped support of the avicularian- mandible 

 which has no membranous margin. 



Explanation op Figbee, 

 Plate 196.— Fig. 2, Two zooecia and avicularium. 



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