610 Cushman: Desmids from New England 



EUASTRUM Ehrenb. 1832 



20. Euastrum crassum (Breb.) Kiitz. 



Length 170 ix ; breadth 85 /x ; isthmus 21 // ; breadth of polar 

 lobe 45 fi. Fairly common, St. Anthony. 



21. Euastrum pinnatum Ralfs. 



Length 120-126 fx; breadth 57-60/*; isthmus 16-18//; 

 polar lobe 31-33 //. Common, St. Anthony. 



a 



22. Euastrum oblongum cephalophorum West. 



Length 170 /i ; breadth 105 \i\ isthmus 26 //> ; polar lobe 

 75 fi. Occasional, Bay of Islands. 



23. Euastrum ampullaceum Ralfs. 



Length 87-1 10 /1 ; breadth 47-72 fi ; isthmus 1 5-20 p. ; polar 

 lobe 22-31 ft. Rose au Rue, Bay of Islands, and St. Anthony. 



This is the most common species of the genus as far as the 

 material examined shows. It was subject to little variation in 

 form. 



24. Euastrum obesum Josh. 



Length 62/1 ; breadth 34 fi; isthmus 8.2//; polar lobe 16/1. 

 Rare, St. Anthony. This is the first record for North America 

 for this species. It was typical in its form and size. 



25. Euastrum divaricatum Lund. 



Length 43 /1 ; breadth 37 // ; isthmus 6 fi ; polar lobe 18/i. 

 Occasional, St. Anthony. 



26. Euastrum elegans (Breb.) Kiitz. 



Length 25 \i ; breadth 1 5 fi ; isthmus 4 //. Rare, Rose au Rue. 



27. Euastrum binale (Turp.) Ehrenb. 



Length 18 fi ; breadth 15 fi. Rare, Rose au Rue. 



28. Euastrum denticulatum (Kirchn.) Gay. 



Length 31/4; breadth 23 fx ; isthmus 5/;; polar lobe 18/i. 

 Common, St. Anthony. 



29. Euastrum pectinatum inevolutum W. & G. S. West. 



■ 



Length 60-62//; breadth 42-44^; isthmus 9-12//; polar 

 lobe 23-25 [x; thickness 25-27//. Very common, St. Anthony. 

 This is the first North American record for this variety. 





