550 Cushman: Desmid flora of Nantucket 



Penium Breb. 1844 



* P. PHYMATOSPORUM Nordst. Loiig. 3 5-40 /-/ : lat. 1 5 - 5- 1 6. 5 /^ : 

 lat. isthni. 13.5 /a Tom Never's Pond, pond near Old North 



Cemetery. 



Closterium Nitzsch, 18 17 



C. cosTATUM Corda. Long. 280/^: lat. 26 n: apex 9/^. 



Almanac Pond. Small. 



C. STRiOLATUM Ehrenb, Long. 200-450 fi : lat. 18-32 a : 

 apex lo/i. Bog pond near Old North Cemetery ; also Almanac, 

 Pest House and Squam Ponds. 



* C, INCURVUM Breb. Long. 62//: lat. 1 1 /a Gibb's and Al- 

 manac Ponds. 



C. Venus Kiitz. Long. 80 /i: lat 10 jx. Wigwam, Pest 



House and Squam Ponds. 



C- Leibleinii Kiitz. Long. 112-190/^: lat. 19-34//: apex 



3-5~5/^' Humniockand Copaum Ponds. 



C* MONiLiFERUM (Bory) Ehrenb. Long. 22^ a: lat 46". 

 Pest House Pond. 



C. ACEROSUM ELONGATUM Breb. Long^ 500 /i: lat 3///: apex 

 5 n. Lily Pond Ditch. 



* C. Lunula intermedium Gutw, Long. 440 /i: lat 65 /i: 



apex 12/^. Gibb's Pond. 



C. ABRUPTUxM West. Long. 200/^. : lat. 1 5.5 /-^ : apex 6 //. 

 Gibb's Pond- 



C. DECORUM Breb. Long, 375 ft : lat 25 // : apex 8.5 /x. Gibb's 

 Pond. 



C. SETACEUM Ehrenb. Long. 235 /^ : lat, 6 /x. Almanac Pond. 



Pleurotaenium Nag. 1849 



P. Ehkenbergh (Breb.) DeBary. Long. 38//: lat bas. 25 /x: 

 apex 20 /i. Wigu'am and Almanac Ponds. 



P. Trabecula (Ehrenb.) Nag. Long. 400 /i: lat. 37/^: apex 

 24 n. Gibb's Pond. 



Tetmemorus Ralfs. 1844 



T. granulatus (Breb.) Ralfs. Long. 146/^: lat. ^4 /x. Wig- 

 wam and Almanac Ponds. 



T, laevis (Kutz.) Ralfs, Long. 70-90 //: lat. 21-22 /x. Lily 

 Pond Ditch ; Copaum and Tom Never's Ponds. 



