OF NEW SOUTH WALES. 125 



On a variety of Trigonia Lamarckii. 



By Rev. J, E. Tenison- Woods, F.G.S. 



I beg to call attention to an interesting variety of Trigonia 

 Lamarckii, which I designate thus : — 



Var. A, Reticulata. Testa tenui, parva, costis acutis, nodulis 

 subspinosis, tota testa peculiariter reticulata. 



This shell was dredged outside Port Jackson Heads by Mr. 

 John Brazier, at a depth of 45 fathoms. The shell is small and 

 thin, and the ribs are sharp, while the nodules are almost spinous. 

 The whole surface is very finely reticulated or perhaps it would 

 be more correct to say shagreened. 



The fact of this variety having sharp ribs is of importance, as 

 a fossil form is found in our Australian Cainozoic rocks, whose 

 main point of distinction from the living T. Lamarckii is the 

 possession of acute ribs and spinous nodules. This is McCoy's T. 

 acuticostata. The present variety cannot be said to be a young 

 shell, because young shells do not present any such peculiarities 

 as may be seen from the specimens exhibited. 



We have six described species of Trigonia in Australia, viz. — 

 T. Strangeii, T. Lamarckii, T. margaritacea, T. pectinata,. T. 

 uniophora, and T. Jukesii. Probably there are only four distinct 

 species, as T. Lamarckii and T. pectinata are the same, and T. 

 Jukesii, Adams is a synonym for T. uniophora of Gray. See Voy. 

 of H. M. S. "Fly." 



There are two or three fossil species in our Australian Tertiary 

 deposits, viz. — T. semiundulaia , McCoy, T. acuticostata, McCoy, 

 and T. Howitti, McCoy. 



On a Tertiary Formation at New Guinea. 



By the Rev J. E. Tenison- Woods, F.G.S. , and Corr. Mem. Jinn. 



Soc. 



During the voyage of the Chevert a tertiary formation was 

 found at Yule Island, New Guinea, and the fossils brought home 

 on the occasion have been submitted to my examination by Mr. 



