14 Transactions of /he Sociehj. 



IJLVACEiE. 



*Prasiola erispa Ktz. On damp ground, valley of the Ganncl, 

 frequent. 



* „ furfuracea Menegh. On a water-wheel in the A^alley 



of the Gannel. 



* „ calophylla Menegh. With the preceding. 

 *Enteromorpha intestinalis Lk. 



Very abundant on moist ground, valley of the Gannel, only slightly 

 above high-water mark. 



*Monostroma Wittrockii Born. 



Along with Prasiola furfuracea and calophylla. Dr. Cooke 

 hesitates on placing this species among fresh-water algae ; it is certainly, 

 according to my observation, entitled to a position there. 



Ulotricha,ce^. 

 Hormiscia moniliformis Eabh. 



,, cateniformis Ktz. 

 Ulothrix zonata Ktz. 



CONFERVACE^. 



*Cladophora flavescens Ag. 

 Conferva fontinalis Berk. 

 ,, bombycina Ag. 

 Microspora vulgaris Eabh. 



„ floccosa Thur. Very commonly more or less of a 



brown tint. 

 *Ch8etomorpha Linum Ktz. 



Fresh- water stream, Mawgan, along with several species of Sjnropyra. 

 Cells varying greatly in colour in the same filament. 



* „ implexa Ktz. With the preceding. 

 *Ehizoclonium Casparyi Harv. With the two preceding species. 



DiATOMACEffi. 



*Epithemia turgida W. Sm. 

 Eunotia Arcus W. Sm. 

 Cymbella affinis Ktz. 

 Surirella biseriata Breb. 



„ linearis W. Sm. 



„ pinnata W. Sm. 



* „ splendida Ktz. 



* „ constricta W. Sm. 

 Nitzschia sigmoidea W. Sm. 



„ linearis W. Sm. 

 „ Amphioxys W. Sm. 



* Amphora ovalis Ktz. 

 Navicula rhomboidcs Ehrb. 



„ rhyncocephala Ktz. 

 ovalis W. Sm. 



