Hollick: Catskill Aqueduct Celebration Exhibit 7 



(c) Brasenia purpurea (Michx.) Casp. Water shield or water target. 



Silver Lake was the only known station for this species on 

 Staten Island. It is now probably exterminated from our local 

 flora. 



(d) Dentaria laciniata Muhl. Cut-leaved toothwort or pepper grass. 



Recorded from but few localities on Staten Island. 



(e) Prunus pennsylvanica L. f. Wild red or pigeon cherry. A single 



tree, now destroyed, was the only one known on Staten Island. 



(f) Diospyros virginiana L. Persimmon. A few of these trees for- 



merly grew on the northwestern border of Silver Lake. They 

 are more or less common in the vicinity of Tottenville and 

 Kreischerville, and a few may be found in the vicinity of Bull's 

 Head a:nd Watchogue. 



(g) Peat from the northeastern end of Silver Lake basin, 

 (h) Semilignitic wood from peat bed. 



( i ) Hickory nuts from peat bed. 



(j ) Wood from the silt at the inner margin of the peat bed. 



(k) Silt from near the center of the lake basin, exposed by draining 

 off the water, covered with a growth of Eleocharis acicularis 

 (L.) R. & S. 



( 1 ) Sandy silt, representing the lowest deposit in the basin. 



(m) Glacial till from beneath the peat bed and silt deposits, represent- 

 ing the original lake bottom. 



3. Pictures illustrating the paper mentioned under Exhibit 2, reproduced 

 from photographs taken by H. H. Cleaves September 29, 1914. 



(a) View, looking northeast across the partly drained lake basin. 



(b) Beginning of a crevasse in the marginal silt. 



(c) A slip, following a crevasse in the marginal silt, exposing the 



original lake bottom. 



(d) Shrinkage cracks in the surface of the silt toward the middle of 



the drained lake basin. 



(e) View, looking across the northeast end of the receding water, 



showing advancing terrestrial vegetation. 



(f) Part of the drained lake basin, northeast end, showing zone of 



Decodon verticillatus (L.) Ell, in the background, Bidens laevis 

 (L.) B. S. P. in the foreground. 

 , (g) Decodon zone on former shore margin of the peat bed at north- 

 east end of the lake basin, 

 (h) Ditch cut through the peat bed, about seven feet in depth. 



4. (a) Silver Lake as it was in 1859. Photograph by H. Hoyer, enlarged. 



View is from the eastern side, looking toward the northwest, 

 (b) View from approximately the same point as that from which the 

 above mentioned picture was taken, showing the marginal grad- 

 ing and the partly drained basin of the lake in preparation for 

 its conversion into a reservoir. Photograph by H. H. Cleaves, 

 September 29, 1914. 



