13 



171. Himantidium ARCUS, Eh. PHtch. Inf. 765. Providence. 



172. Meridion constrictum, Ralfs PHtch. Inf. 768. ' Providence. 



173. Odontidium h y emale, Kutz. PHtch. Inf. 775. 0. turgidulum. 



Providence. 



174. Fragii/laria capucixa, Kutz. PHtch. Inf. 776. Providence. 



175. pectixalis, Eh. PHtch. Inf. 777. Providence. 

 176 virescexs. Half s. PHtch. Inf 777. Providence. 



177. Syxedra ulna, Eh. PHtch. Inf. 788. Providence. 



178. Serirella biseriata, Breb. PHtch. Inf. 794. (8. bifrons.) Provi- 



dence. 



179. Tabellaria flocculosa, Kutz. PHtch Inf. 807. Providence. 



180. Thwaitesii, Olney n. s. Allied to C flocculosa, 



but differing in infliation and end view. Provi- 

 dence. 



181. Cocconema lanceolatu3I, Eh. PHtch. Inf. 877. Providence. 



182. cymbiforme, Eh. PHtch. Inf. 818. Providence. 

 L83. Sphexella rostellata, Kutz. PHtch. /m/. 886. Providence. 

 184. GrOMPHONEMA constrictum, Eh. PHtch. Inf. 887. Providence. 

 L85. trtjncatum, Eh. PHtch. Inf. Providence. 



L86. minuttjm, Eh. PHtch. Inf. Providence. 



187. Navicula gracilis, Eh. PHtch. Inf. 906. Providence. 



188. viridis, Kutz. Providence. 



189. Stauroxeis Phjsnicenteron, Eh. PHtch. Inf. Providence. 



Omission. 

 42. bis. Delesseria sinousa, Lamour.-Harv. Bor. Am. 2. 93. 



Hammond, Angell & <',>.. Printers. 



