THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTORY, 



[THIRD SERIES.] 

 No. 4. APRIL 1858. 



XXI. — Notes on the Palceozoic Bivalved Entomostraca. No. IV. 

 Some North American Species. By T. Rupert Jones, F.G.S. 



[With two Plates.] 

 [Continued from 2nd Series, vol. xvii. p. 101.] 



The Entomostraca which I propose to describe in this communi- 

 cation have been brought from different parts of North America 

 at different times, and kindly submitted to me for examination. 

 The series of specimens from Canada were placed in my hands, 

 in 1851, by Sir W. E. Logan; and I intended to describe them 

 at once, but found that, without a more definite knowledge of 

 the Beyrichice and allied forms already noticed by geologists, I 

 could not do justice to the work. The Notes I., XL, & III., on 

 Palaeozoic Bivalved Entomostraca, published in former volumes 

 of the ^ Annals,^ have been the result of my inquiries on this 

 subject ; and at last I felt more capable of handling the series 

 set before me. In the meantime, other North American mate- 

 rials came to hand. A portion of these specimens have taken 

 their place as illustrative of generic characters in the former 

 papers ; and a portion remain to be noticed here, including the 

 smaller Entomostraca in the limestone of Beechey Island, a few 

 specimens from the United States in the Geological Society^s 

 Museum, and, more especially, a valuable series of beautiful 

 specimens from Pennsylvania, which Prof. H. D. Rogers has 

 most considerately and kindly permitted me to describe as illus- 

 trative fossils of the Geological Survey of that State. 



Several species of bivalved Entomostraca have been already 

 Ann. S^^ Mag. N. Hist. Ser. 3. Vol.'u 16 



