A HISTORY OF SUSSEX of the rarer kinds, and Mr. Roper examined those of the Cuckmere. Of the Desmideas, D. Swartzii, Ag., was discovered near Rotherfield by Borrer. Doubtless our rivers contain many unrecorded species. In the Ems I have noticed Batrachospermum in abundance. It comes to maturity both in spring and autumn. From our estuaries, just above the influence of the tide, additions to our lists are still to be made. Of the Diato- maces about 150 have been recorded. This list is arranged according to Harvey's Manual. CYANOPHYCEi^ Chroococcace^ Protococcus irridis, Ag. Hastings — pluvialis „ „ NOSTOCACE^ Nostoc caeruleum, Lyngb. Hastings — variegatum, Moore. „ OsCILLATORIACE^ Oscillatoria limosa, Vauch. Hastings ■ — ■ autumnalis, Ag. Eastbourne Lyngbya muralis, Ag. Hastings — ferruginea, Ag. Brighton RlVULARIACE^ Rivularia nitida, Ag. Brighton CHLOROPHYLLOPHYCE^ Palmellace^ Palmella cruenta, Ag. Hastings ZOOSPORES CoNFERVACEi^ Cladophora glomerata, L. Hastings ■ — crispata, Ag. „ Conferva crassa, Ag. „ CONJUGATEiE Zygnema curvatum, Ag. Henjield — quininum, Ag. Hastings OOSPOREiE Vaucheriace.^ Vaucheria sessilis, De C. Hastings Carpospore^ Drapurnaldia plumosa, Ag. Hastings Batrachospermum moniliforme, Ag. Hast. — atrum, Borr. Brighton MARINE ALG^ The marine algae do not abound on the Sussex coast as on the shores of our western counties. We meet with comparatively few sea- weeds as we proceed eastward until we approach Brighton and Beachy Head, where they become more numerous, as well as at St. Leonards and Hastings further on. We have lists of them by some of our societies and an excellent account by Mrs. Merrifield in her Natural History of Brighton and its Vicinity, but a good monograph of the Sussex algs is still a desideratum, and in such should be differentiated those growing within tide marks from waifs and strays. The occurrence of algas in certain localities seems in some cases to be periodical, and as instances Mrs. Merrifield states that in 1849 the rare and beautiful Griffithsia barbata, Delesseria hypoglossum, Halymetna ligulata, Ginatinia f ur eel lata, the lovely Naccaria Wiggii and the Dudresnaia coccinea, usually considered so rare, were found at Brighton abundantly, and again in 1858 says: ' During this present year the collectors of seaweeds have had an abundant harvest, no less choice in quality than prolific in species. Among the rarer algse I picked up Arthrocladia villosa, Sporochnus pcdun- culatus, Cutleria multifida and Taonia atomaria, the seaweed which resembles a peacock's tail ; but the greatest rarities in this district were Griffithsia barbata, Seirospora Griffithsiana and CalUthamnion plumula, neither of which were previously found at Brighton. Dudresnaia coccinea was 62
