54 Prof. T. E. Jones and Dr. H. B. HoU on 



An evergreen tree, 8-16 feet high, with a trunk 8 inches 

 in diameter : leaves l|-4 inches long, 5-12 lines broad, on a 

 petiole 1^-2 lines long; peduncle IJ-IJ inch long, gradu- 

 ally thickening to the summit ; sepals 4 lines long, 3 lines 

 broad, free and attached to the margin of the thickened apex 

 of the peduncle, each with seven parallel nervures ; petals 

 9-11 lines long, 4-5 lines broad, including the inflected 

 margins, with three apical teeth 1 line long, glabrous ; co- 

 lumnar disk 1 line high, 2 lines in diam., glabrous ; filaments 

 3 lines, anthers 5 lines long ; scabridlj rugulose ; ovary 3 lines 

 long, 2 lines broad ; style 4-7 lines long ; capsule 8-10 lines 

 in diameter ; seeds at least 2 lines in diameter, attached to the 

 central column*. 



VII. — Notes on the Palceozoic Bivalved Entomostraca. 

 No. VIII. Some Lower-Silurian Species from the Chair of 

 Kildare, Ireland, By Prof. T. KuPERT JoNES, F.G.S., 

 and Dr. H. B. HoLL, F.G.S. 



[Plate Vn.] 



In 1863 Mr.W. H. Baily, F.G. S., Paleontologist of the Geologi- 

 cal Survey of Ireland, sent us, from the mountain near Kildare 

 known aS the Chair of Kildare f, some of the grey, crystalline, 

 encrinital limestone, of '^ Caradoc-Bala " age, containing the 

 minute fossils referred to by Prof. M'Coy, in Sir R. Griffith's 

 ^ Synopsis of the Silurian Fossils of Ireland,' p. 58, as Cythere 

 phaseolus of Hisinger. In 1865 Mr. Joseph Wright, F.G.S., 

 of Cork, visiting the Chair of Kildare, brought away a quan- 

 tity of this limestone to examine at his leisure ; and having 

 broken it up and picked out the separate fossils, he found 

 many of these little Entomostraca, and sent us a liberal supply 

 of them for examination. These specimens are all smooth 

 calcareous representatives of closed carapaces : they may be 

 said to consist of the carapace-valves replaced by calcite and 

 filled with the same ; while a very thin film of pulverulent 

 calcareous material sometimes represents the outermost portion 

 (or surface) of the valves. 



It has been difficult to find alliances for these Lower- Silu- 

 rian Entomostraca, simple as they are in form and structure ; 

 but since our determination of the Silurian Primitice of the 



* A representation of tliis plant, with particulars of its floral structure, 

 will be seen in plate 83 A of my ' Contributions. ' 



t See the explanatory memoir entitled ^ Data and Descriptions to ac- 

 company Quarter-Sheet 35 N.E. of the Map of the Geol. Survey of Ire- 

 land,' 1858. 



