President's Address. 21 



one already known, the C. quadmta (^PCoy), and an nn- 

 described form called C. Pentlandica. In addition to these 

 shells were a Gasteropod and two Cephalopods, raising the 

 total number of Mollusca at all well defined to about seventy- 

 three or -four species. 



We must not quit the Silurian rocks of the home county, 

 however, without reference to the later work of the Geologi- 

 cal Survey. Professor Geikie was fortunate in securing the 

 services of a most able and enthusiastic collector, by whom 

 the whole of the localities previously known, and several new 

 ones, were diligently searched, and large and varied collec- 

 tions made. I refer to my friend Mr James Bennie. In 

 collecting from these beds Mr Bennie has wisely adopted 

 the plan followed out by Messrs Henderson and Brown, and 

 taken the strata bed by bed at the various exposures of the 

 rocks. His collections, I am sorry to say, have never been 

 thoroughly investigated, and no part of the results published. 

 There are, I know, several new and interesting shells, belong- 

 inu: to the class Lamellibranchiata, besides forms in other 

 classes, which would well repay study. X selection of these 

 may be seen in the Museum of Science and Art. 



The Molluscan Fauna of th^ great Black Shale group of 

 the south of Scotland — the jNIoffat series — has hitherto proved 

 of the most scanty description. The first shell recorded from 

 these black shales was, I believe, a small Brachiopod, called 

 by M'Coy Siphonotrcta micnla, and very characteristic of 

 certain portions of the Llandeilo series in Wales. It was 

 disco vereil by Professor Harkness, and specimens were pre- 

 sented to the Museum of Practical Geology in Jermyn 

 Street.* About the same date Mr J. Stevens found in the 

 Moftat shale a TentaciUites,f a small elongate shell, at one 

 time regarded as the tube of a tubicolar worm, but now 

 believed by our best authorities to be a I'ree-swimming 

 mollusc of the class Pteropoda. 



Later on a second Brachiopod was discovered by our 

 president, Professor H. A. Nicholson, in the black shales of 

 Dobb's Linn, Moftat. The specimens were sent to Mr David- 



t 



Cat. Foss. i\lus. Pract. Geology, 1S65, ]\ 17. 

 Geol. Mag., Sept. lS6r., p. 431. 



