Victorian Fossils. 11 



Order CTENOBRANCHIATA. 



Sub-order PLATYPODA. 



Genus Xenophora, Fischer. 



Fam. XENOPHORIDAE. 



Sub-genus Tugurium, Fischer. 



Xenophora (Tigurium) tatei, Harris. 



Xenophora {Tugurium) tatei, Harris, 1897. Cat. Tert. Mol- 

 lusca. Brit. Mus., pt. i., Australasian Tertiary Mol- 

 lusca, p. 254, pi. vii. figs. 7a, h. 



Xenophora tatei, Harris, Hedley, 1903. Mem. Aust. Mus.,. 

 Mem. iv., pt. 6, p. 357. 



Observations. — This species is very remarkable for its great per- 

 sistence in time. It first appears in the Oligocene of Muddy Creek,, 

 where it is of moderate dimensions. In the Janjukian, of the Murray 

 River Cliffs and elsewhere, it attains an enormous size. It has not 

 been found in the Kalimnan or Werrikooian to my knowledge, but 

 reappears in recent dredgings, as recorded by Hedley. 



The Oligocene Specimens. — In the Dennant Collection at the 

 National Museum is a fair series of specimens from the lower beds- 

 at Muddy Creek. The smallest example has a diameter of 15 mm., 

 whilst the largest measures 45 mm. The attached fragments on the- 

 surface of the shell are chiefly polyzoa and Siliquariae, but the latter 

 may be idioparasitic; that is, growing upon the adventitious frag- 

 ments. Newport, Altona and Mornington are also mentioned as locali- 

 ties by Dennant and Kitson.is In the National Museum collection there' 

 are also examples from Grice's Creek, which have Limopsis and Dimya 

 shells attached. 



Janjukian Examples. — Dennant and Kitson's Listi9 includes the 

 following localities: Camperdown, Shelf ord, Lower Moorabool. 



A fine example of X. tatei in the National Museum from Bird 

 Rock Cliffs, presented by Mr. F. A. Cudmore, is almost entirely cov- 

 ered by fragments of bivalves. The same donor presented an enor- 

 mous specimen from the Murray River Cliffs, a quarter of a mile above- 

 Morgan (lowest bed). — See wall-case, Australian Fossil Gallery, Nat. 

 Mus. This megalomorph shows that the Janjukian fauna was at its acme- 

 of development at this phase, and dwindled down in size to the present 

 day to the same extent as when it existed in Oligocene times. The Murray 

 River specimen, which is a cast and mould with fragmental covering, 

 measures 115 mm. in diameter between the extreme surfaces of the 

 mould. The internal cast is 98 mm. in diameter. The height of the 

 shell was approximately 70 mm. The entire shell with encrusting- 

 fragments (small oysters) measures 22 cm. 



18. Rec. Geol. Surv. Vict., vol. i., pt. ii., 1903, p. 113. 



19. Op. cit., p. 113, 



