= ae 
= 8 
FOSSILS FROM THE PALHOZOIC ROCKS OF N.S.W. 253 
Class—PTEROPODA. 
Genus Tentacutites. Schlotheim, 1820. 
Obs. The late Rev. W. B. Clarke, F.R.S., &c., determined three 
species of this genus in the Australian paleozoicrocks,' viz., 7. annu- 
noteworthy that Prof. De Koninck did not describe any species of 
Tentaculites in his recent work on Mr. Clarke’s New South Wales 
Fossils. Prof. Liversidge has forwarded to me two handsome 
sing these masses are preserved as sections of the tubes, and not in 
relief, it is difficult to express an opinion as to their identity ; but in 
writers remarks’ of 7. irregularis (Hall)—“ On this same specimen, 
which has a length of five inches and an averag' breadth of little 
more than one inch, more than five hundred individuals may. 
counted ; and the layer beneath for the thickness of a quarter of 
an inch is composed almost entirely of these fossils, giving more 
than ten times as many as can be seen upon the surface. * ¥ drome 
The layers thus covered are known in numerous places over an 
extent of country from thirty to fifty miles, showing the myri 
of these creatures that flourished upon the bottom of the ancient 
sea.” Prof. Nicholson states’ that 7. jissurella of the Devonian 
rocks of America is “remarkable as occasionally occurring in such 
extraordinary profusion as to actually form beds of limestone.” 
Tn the Australian species the form of the shell is an elongated and 
slender one, the annulations are numerous, sharp, and project some 
distance laterally, but I have not been able to determine whether 
intermediate ornamenting strie existed. 
The preservation of this species in limestone has enabled me to 
study the structure of the shell-wall by means of thin sections 
Prepared for the microscope. This subject does not appear to have 
n investigated to any great extent, one of the few writers who 
have described it Dr. Richter of Saalfeld. In a paper on 
bad Thuringian Tentaculites, he states that the structure was not 
18. Gold-fields, N. S. Wales, 1860, p. 286 3 
; Pal. New York, i ate iees 
an. of Paleontology, 2nd ed., ii, p. 52. 
é 
