44 



some respects resembling the form I have lately described 

 as R. Broivnii,^ but lower in the spire, and therefore 

 probably distinct. It is very desirable that additional 

 examples of this fossil should be obtained, with the view of 

 determining its systematic position with greater accuracy, 

 Loc. — Zeehan, in a white quartzite. 



Pteropoda. 



Genus Tentaculites, Schlotheim. 



(Petrefactenkunde, 1820, p. 377.) 



Tentaculites, sp. ind. 



PL, Fig. 27. 



Ohs. — This elegant genus is represented by a very large 

 number of external impressions. Casts taken from the 

 latter display a remarkably elongate and delicate form, 

 extending to a fine needle-point, but without any trace of 

 the bulbiform embryonic shell. The characteristic annu- 

 lations are about one-fourth or one-fifth millimetre apart, 

 or four to five in number in the space of one millimetre. 

 The interannular spaces are delicately transversely striated 

 as usual in the genus. The annulations were very sharp, 

 and apparently came to a fine edge. 



Specific identification from the condition of the specimens 

 is impossible, but it is a smaller form than that figured ^ 

 by myself from the Siluro-Devonian rocks of the neigh- 

 bourhood of WelHngton, N. S. Wales. 



Loc. — Heazlewood and Zeehan, in a blue-grey schistose 

 rock. 



5.— AGE. 



The species detailed in the foregoing pages present both 

 a Lower and an Upper Silurian facies, but with a pre- 

 ponderating tendency towards the latter. I think it not 

 impossible that they represent a series of beds homotaxially 

 equivalent to the lower portion of the Upper Silurian. 



» S. Australian Pari. Papers, 1891, No. 158, p. 9, PI., f. 1-3. 

 8 Journ. R. Soc. N. S. Wales, 1880, XIV., p. 253, pi., f. 10. 



