146 report — 1884. 



Bry.,' ' Ann. Mag. Nat. Hist.' April, 1879, p. 275), after inspecting a 

 Northern H. violacea from the cabinet of Rev. A. M. Norman, there 

 is ' hardly anything in common ' with the two forms. He also remarks 

 that ' the genns Filisparsa is, as pointed out by D'Orbigny, intermediate 

 between Hornera and Idmonea. ... I am, however, somewhat in doubt 

 as to whether the genus will permanently stand' (lor. cit. p. 275). Of 

 this I am not so certain. Filisparsa Uibulosa, Bask and Waters, and 

 F. various, Reuss, are neither Idmonea nor Hornera, and it seems to me to 

 be far preferable to characterise an intermediate form by a generic name, 

 rather than simplify too much our generic nomenclature. If, however, 

 it can be found that, in dealing with fragments of species of the genus 

 Hornera, the differences in character arise from differences of growth 

 — like the Fenesfella of the Carboniferous rocks, then these remarks will 

 have no weight ; but so far as I have been able to study species of the 

 genus Hornera and Filisparsa they appear to me as distinct. 



There are a few fossil species of Hornera found in material from 

 several localities in Australia, especially the Yarra Tarra district, but as 

 these have not as yet been described it would appear rather invidious to 

 anticipate Mr. Waters's work, the completion of which — Cyclostomatous 

 Forms— has been -promised by him. 1 



Before concluding these remarks, it may be well to refer the student 

 to Mr. Hincks' matured opinion of the genus Hornera (loc. cit. p. 467), 

 because he includes in the one genus the true typical Hornera with its 

 ' wavy anastomosing ridges,' and the tubular H. violacea, Sars, which is 

 destitute of the characteristic ' fibrous crust ' found in H. lichenoides, 

 Linnreus. 



Genns Hobxera, Lamouroux. 



= Betepora, (pt.) Goldfuss ; Sipliodieiam, Lonsdale. 



Zoarium erect, ramose, sometimes reticulate. Zoa/cia tubular, opening 

 on one side only of the branches, disposed in longitudinal series, the 

 celluliferous surface often traversed by wavy anastomising ridges. 

 Ocecium a distinct chamber, not a mere irregular inflation of the surface 

 of the zoarium, placed dorsally or in front. 



The care with which Mr. Hincks has drawn up the above diagnosis 

 ought to satisfy the ordinary critical student of Fossil Polyzoa, but the 

 most valuable element of structure is the peculiar ocecium. In the 

 absence of this, there are other elements which may serve as a guide and 

 a check to overhasty identification. In his work on the ' Bryozoa of the 

 Maastricht Beds,' &c, Hagenow gave a synopsis of the whole of the then 

 known Hornera, ranging from the Recent to the Upper Silurian. In the 

 last formation the Hornera orassa,* Lonsdale, is the sole representative; 

 excepting this no true Hornera is given by the author below the ' Kreide- 

 formation.' I reproduce below Hagenow's list, because in his work he 

 only describes and figures one species. There are several Hornera 

 described by Reuss and Busk, and there are still many undescribed forms 

 among the Australian Polyzoa of Mr. A. W. Waters, and also in my own 

 cabinet. 



B. Tertiarformation. 



S3. Hornera Hippoltta, Defrance. 

 84. „ gracilis, Philippi. 



J See remarks ante. " This is not a Hornera, but a T/iamnisnts. 



