188 PROCEEDINGS OP THE ACADEMY OP 



rsena, L., et c'est moi qui reellement ai nomine" l'espece ; 3 parce qu'il n'est 

 pas permis de donner des noms propres aux varie"tes, et Ton ne doit pas en 

 sanctionner l'usage ; 4 parce que c'est moi qui ai fait reconnaitre cette 

 espece, en la comparant avec les Sph. Becuna, Barracuda, Guaguanche, Picu- 

 dilla, dans mes M6m. sur l'Hist. Nat. de Cuba, vol. 2. Bloch n'a rien ajoute 

 a Parra, dont il a copie* la figure. 



$IayJ>. Mr. Lea read part of a letter from T. Rupert Jones, F. R. S., 

 Prof, of Mineralogy and Geology in the Royal Military College at Sandhurst, 

 England, in which he informs Mr. Lea that he has been engaged many years in 

 the examination of fossil Estheriee, and was about to publish a monograph in 

 which he recognises the species described by Mr. Lea, as Posidonia ovata, from 

 Phoenixville, Pa., and those near Richmond, Va., in the " Estherian shales " 

 (Trias) of these localities, and states that " Estheria ovata, Lea, is as important 

 in the palaeontology of North America as E. minuta is in Europe," but that its 

 exact geological place is not defined without difficulty. 



Prof. Jones also communicates to Mr. Lea, a very important observation in 

 recognizing Cypricardia Leidyi, Lea, published in our Proceedings in 1855. 

 Some specimens of this " enigmatical fossil " were found in the carboniferous 

 strata in England, 26 years ago, and it is also almost as rare there as it is here. 

 The specimen described by Mr. Lea was found by Dr. Leidy, and is the only 

 one which has been found in this great mass of red shale, (Formation No. xi. 

 of the Penn. Survey.) There was always a doubt in Mr. Lea's mind, whether 

 this species belonged to Cypricardia, but in the absence of observation as to 

 the teeth, it was impossible to decide with certainty. Professor Jones finds 

 two varieties of the same species in the Coal Measures near Manchester and in 

 Fifeshire, and considering that they do not belong to the genus Cypricardia, 

 proposes to form them into a new genus, and in his paper to be published by 

 the Palfeontological Society, he will give diagnoses and illustrations of the 

 American species and European varieties, under the name of Leaia Leidyi. 

 That from Lancashire he calls variety Williamsoniana, and that from Fifeshire, 

 as variety Salteriana. 



July 7th. 



The President, Mr. Lea, in the Chair. 

 Twelve members present. 



July \th. 

 The President, Mr. Lea, in the Chair. 

 Eleven members present. 



July 2\st. 



The President, Mr. Lea, in the Chair. 



Thirteen members present. 



Mr. Kilvington presented to the notice of the Academy specimens 

 of Rhus Cestricus, Darl., a plant first detected by him. 

 The following papers were presented for publication : 



[July, 



