Zoology.] NATURAL HISTORY OF VICTORIA. [Polgzoa. 



transitional. It is not capitate, but has a broad calcareous basis, 

 clearly representing the pedicle of the ordinary capitate form. 

 The mode of attachment is peculiar, the zoarium being fixed by 

 numerous radical tubes springing from the backs of the cells. 



Explanation of Figures. 

 Plate 117. — Fig. 6, front view of portion of specimen. Fig. 7, back view, showing con- 

 nection of each zooecium with six others by short, thick, calcareous tubes. Fig. 8, single zooecium 

 from another specimen, showing a few radical fibres. 



Plate 117, Fig. 9. 



AMPHIBLESTRUM PATELLAKIUM (Moll sp.). 



Description. — Zooecia slightly separated and connected by short tubes, oval and 

 lozenge-shaped ; margins raised, crenulated ; lower two-thirds filled in by a minutely 

 granular calcareous expansion ; aperture nearly semicircular, occasionally somewhat 

 trifoliate. Ocecia rounded, smooth, with a thickened rim below. 



References. — Mollia patellaria, Smitt, Flor. Bryozoa, Pt. ii., p. 12, fig. 72 = 

 Diachoris patellaria, Waters, Ann. and Mag. Nat. Hist., Feb. 1879 = Membrani- 

 por a patellaria, P. H. MacGillivray, Tr. Roy. Soc. Vict., Dec. 1881. 



Port Phillip Heads. 



This species agrees with Beania and Diachoris in nothing but 

 the disjunction of the cells ; otherwise it is undoubtedly an Am- 

 phiblestrum, allied to A. Rossellii. It agrees perfectly with the 

 form described by Waters, from the Bay of Naples, as Diachoris 

 patellaria var. multijuncta. The cells are only slightly separated, 

 and are sometimes so close that the connecting tubes cannot be 

 distinguished. Each cell is connected with the adjacent ones by 

 usually about twelve tubes. In the typical form, as figured by 

 Smitt and Waters, the connecting tubes are much fewer. These 

 naturalists consider Heller's D. simplex as the same species, which 

 they refer to Moll's Eschara patellaria. I have not seen Moll's 

 work, but Heller's figure certainly looks very different. No 

 avicularia have been seen. 



Explanation of Figures. 

 Plate 117. — Fig. 9, group of zooecia, magnified. Fig. 10, portion of another specimen, 

 showing ooecia. 



I am indebted for the specimens and descriptions of the Polyzoa 

 on this plate to Mr. MacGillivray. 



Fkederick McCoy, 



[ 70] 



