14 NATIF®AL aiSTOET, 
Journal of the Academy of NaitH'ral Sciences Of PMadelpii&^i Owdmtied. 
Observations on the Genus Eriogonum, &c., concluded. 
Character of a Nfew Genus, aild Descriptiohs of three New Species upon which it is 
formed; discovered in the Atlantic Ocean, in the months of March'and April; 1816, 
laf. 22 ? 9', byC.- A. Le Sueuri 
Description of three New Species of the Gehus Raja, by C.-A. Le Sueurv V 
Some Account of the insect known by th'e name of Hessian Fly, and of a parasitic 
• Insect that feeds on it, by Thomas Say. . : , 
On a New Genus of the Crustacea, and, the Species in which it is established, by 
Thomas Say. 
An Account of an American Species of the Genus Tantalus, or Ibis, by George Ord. 
An Account of the Crustacea of the United States, by Thomas Say. 
An Account of the Crustacea of the United States, continued. 
A short Description of five (supposed) New Species.of the Genus Mursena, discovered 
by Mr., Le Sueur, in the year lSl6, by C. A. Le Sueuf. 
Description of two New Species of the Genus Gad us, by the same. 
Description of a.New Species of the Genus Cyprinus, by the same. : •: 
An Account of an American Species: of. Tortoise; not noticed in .the Systems, by the 
same. ; ,,. , . ( ,i 
A; New Genu^ of Fishes, of the Order Ahdominales, proposed under the nameCatos- 
tomus, and the characters of this Genus, with, those of its Species,: indicated, by 
the same. 1 ' nrculi 
An Account of the Crustacea of the United States (continued). 
Catostomus, d New Genus of Fishes (concluded). . , ! . . . : • . 
An Account of two New Genera of Plants/and of a Species of Till8ea? ; gnd another 
of Limosella, recently discovered on the banks of the Delaware, in the vicinity of 
' Philadelphia, by T^os. Nuttall. 
pfe’seriptiohs of N,evr ; Species of Land and Fresh-watbr;Shells of the United Stktes, by 
Thomas Say. : . 
Descriptions of four New Species, and two Varieties', of the,GehusHydrargira,hyG. A. 
Le Sueur. 
Observations on the Geology of the West India Islands, from Barbadoes to Santa 
Cruz, inclusive, by William. Maclure. 
Observations on several Species of the Genhs Actinia; illustrated by Figures, by G. A. 
Le Sueur. 
An Account of the Crustacea of the United States (continued). 
Observations on several Species of the Genus Actinia (continued.) 
Description of Collinsia, a New Genus of Plants, by Thomas Nuttall. 
Act of Incorporation. 
Constitution. 
Catalogue of the Library. 
List of Donors to the Library. . 
List of Donations to the Museum, 
List of Donations to the Apparatus. 
Tot i. Part II. 11 Plates. 8vo y pp. 221 to 5G3. Philadelphia, 18l8. 
. CONTENTS. , ' 
Officers of the Academy of Natural Sciences for the year 18i8, 
Descriptions of several New Species of North American Fishes, by. C. A. Le Sueur, 
An Account of the Crustacea of the : United .States, by Thomas Say: (continued), 
Observations oh two Species of the Genus Gracula of Latham, by GeOrge Ord. 
Report of a Committee on a New Hydrostatic Balance, invented by Isaiah Lukens)and 
submitted to the Acadehly; y . > 
Essay on the Formation of Rocks; or, an Inquiry into the Probable Origin of their 
present Form and Structure, by William Maclure (continued). 
, Account of two New Genera and several New Species of Fresh-water and Land Shells, 
by Thomas Say. 
Essay oh the Formation of Rocks: or, ah Inquiry into the Probable Origin of their pre¬ 
sent Form and Structure* by William Maclure (continued). 
Observations of a New Genus of Fossil Shells, by C. A. Le Sueur. 
Ah Account of the Crustacea, ■ of the'United: States-, .by Thoinas Say : (Continued). 
Observations on the Genus Glicine 'and some of its kindred Genera, by S. Elliott. 
Essay oh the Formation of Rocks; of, an Inquiry into the Probable Origin of their 
present Form and Structure, by William MaclufO (concluded). ■' , 
An Account of the Florida Jay of Bartram, by George Ord. 
Description of several Species of North. American'Amphibia, accompanied with Ob- 
•» • :i servations,"by l Jacob Green. 
Description of several New Species of North American FishOs, by 0. A. Le Sueur 
(continued). 70l‘X<0 It ‘in /: 
