61 



Lecture 14, A\ag\ist 1, 1900. 

 'r».. Bl"bliQgrapliv of Long ^ Island . 

 Mather : Geology, 1st Dlst, N.Y. 184;5. 



Upliam : Terminal moraines of North American Ice Sheet. Am. J.Bci .TIL, /?. 

 I-Terrill : Geography of Long Island. Am. II. Y. Acad. Science, m.,V\'V\5t^/^^<5- 

 Hollick : Cretaceous Format ion of Lojig Island. 

 Jeliiffe : Flora of Loiig Island, l[j99. 



Long X93-ahd. 

 Long Island. 120 miles long and from 10-20 miles wide. Two 

 distinct parts. Northern, hilly, southern flat. Hills begin at 

 Bay Ridge, extend to Roslyn, N.E., then east to Sag Harbor -and 

 thence to Ilontai^.k Point, ^alleys extending across harbor from the 

 bays ; fewer streaias than valleys on north shore. 30 valleys have 

 be'^n counted. On the south shore valleys probably remnants of old 

 glacial streams. ITo lakes or rivers on the island, but many springs 

 due to fact that upper soil is sand and gravel preventing surface 

 drainage and under layer of clay. Hence drainage of Long Island is. 

 like that of a limestone region. Few -.ponds, but many swamps. One 

 lake, Ronkonkonia — 3 miles. Many indentations on north shore, 

 irregular coast-line made more irregu.l.ar by post-glacial action as 

 at Lloyd 's point. 



