430 Eev. A. M. Norman on the Voyage of Unio Thomsoni. Testa ovata, postice aliquanto acuminata, insequilateralis, flavescens vel rosaceus, sordide rosaceo obscure radiata, epidermide tenui olivacea obtecta, concentrice striata, prope marginem dorsalem granose radiatim distincte utrinque corrugata. Margo dorsalis postice declivis, antice subsinuate descendens ; margo ventralis valde arcuatus, postice vix sinuatus. Umbones parvi, acutiusculi, conciime corrugati, ad |-longitudinis siti. Dentes cardinales parvi, irregulariter bifidi vel tripartiti, rugosi, striati ; posteriores graciles. Pagina interna cseruleo-alba, roseo radiata vel pur-pureo-fusca. Long. 15 millim., lat. 21 ; diam. 10 millim. Hab. Lake Tanganyika {Thomson). LVII. — Notes on the French exploring Voyage of l Le Tra-vailleur ' in the Bay of Biscay. By the Rev. A. M. Nokman, M.A., F.L.S., &c* In June last a Commission was appointed by the French Government for the purpose of exploring the great depths which captains and Spanish fishermen affirmed existed in the Gulf of Gascony, off the coasts of Cantabria and the Asturias. The members of this Commission were Professor Milne-Edwards (President), Professor Alphonse Milne-Edwards, the Marquis de Folin, Professor Vaillant, Professor Marion, Professor L. Perier of Bordeaux, and Dr. Paul Fischer. M. Jules Ferry, the Minister of Public Instruction and Science, did my friend Dr. Gwyn Jeffreys and myself the honour of inviting us to act with this Commission as " colla-borateurs etrangers," and to accept hospitality on board the Government steamer ' Le Travailleur/ which was placed at the disposal of the Commission for the last fortnight of July. 'Le Travailleur ' is a paddle-steamer of about 1000 tons, with a complement of officers and men, which was increased to 145 for the expedition, additional hands being engaged, so that there might be no cessation night or day in the sound-ings and dredgings. She was carefully fitted up with every scientific appliance necessary for such an expedition, and was most admirably handled by Captain Richard, her commander, and his efficient staff of officers, all of whom threw themselves * Paper read at Meeting of the British Association at Swansea, August 31, 1880.