212 PERORT— 186G. 



that ileeting 13 species have been added to the Est, distributed as follows : 

 — Of the Cephalopoda, EJedone octopodia, Sepiola Rondeletii, Lollgo vulgaris, 

 and Bepla officinalis ; of the Prosobranchiata, Mangelia hrachystoma, M. ne- 

 bula and M. lipvigata (besides M. pjiramidalis in a fossil state), Defrcmcia 

 purpurea, ani liissoa costata \ of the Laniellibranchiata, Area pectunculoides 

 and Leda pygnicm (two valves of each), both dredged off the Ord of Caith- 

 ness, and Scrobicularia nitida. 



It may be worth mentioning, that in Cromarty Baj- the dredges were put 

 down in four fathoms of water, and brought up alive Rissoa costuta in 

 abundance, Natica Alderi, Leda minuta, Arinus jlexuosus, iScrohicuJaria 

 nitida, Corbula gihba, and Panopea plicata. 



Of the Crustaceans (Brachyura) found on this and former occasions, maybe 

 mentioned Hyas coarctatus in spawn (July, October, and November), Eury- 

 nome aspera, Portunus puher, P. depurafor, P. marmoreus, Ebalia Pennantii, 

 E. branchii, Atelecyelus heferodon in groat numbers, and Lithodes Maia. 



Of Anoraoura are the following : — Pagurus lo'vis, Porcellana platychelex 

 (one specimen) and P. hngicomis in great abundance, Galathea strigosa and 

 G. disperse, Munida liondeletii, CaUianassa suhterranea, Gebia deltura, Ca- 

 loearis Macanlrea>, Nephrops norvegicus, and Pandalus annidicornis. 



The examination of the Stomapoda has yielded Vaunthomsonia cristata, 

 Ewlora, n. s., and Bodotria arenosa. 



The Amphipoda normalia, so far as examined, have given Ampelisca 

 Gdimardii, Urothoii viari)ius, Ampliitho'e rabricata, and Corophium BonelU, 

 Many of this class remain unexamined. 



Of the Isopoda aberrantia may be mentioned Tanais Dulongii. The Iso- 

 poda are Cerolana hertipes, u^ga bicarinata, and Rocinela Banmonieiisis. 



A Holibut was caught, and off it was taken Lepeophtheinis Idppoglossi. 



The Annelida are as yet unexamined. 



Few species of the Echinodermata came up, the only noteworthy one 

 being Bi'yssiopjsis lyrifer. One specimen of Uraster rubens may be men- 

 tioned for its size. It measured 18| inches across. 



The Polyzoa and Hydrozoa yielded nothing worthy of remark, except a 

 fine specimen oi Rhizostoma pulmo. 



The only specimen of the Actinozoa dredged was a very young Adamsia 

 palliata. As the ActinioB, not contained in the former Keport, are mentioned 

 in the 'Actinologia Britannica,' it is deemed unnecessary to enumerate them. 



The Committee have to return their warmest thanks to Dr. Gray, 3Ir. 

 Bate, Dr. Bowerbank, and the llev. A. il. Norman. Without their help, so 

 freelj- and so kindly given, this Keport, as well as the former, would not have 

 been half so complete. The Committee have to express their regret that the 

 weather was so unpropitious, as they have every reason to think that much 

 more would have been accomphshed had they reached one or two of the 

 banks on which they were anxious to dredge. 



Report of the Committee on the Transmission of Sound- Signals under 



water. 



At the last Meeting of the Association a Committee, consisting of the Eev, 

 Dr. Robinson, Professor 'V^Tieatstone, Dr. Gladstone, and Professor Hennessy, 

 was appointed to Report on the transmission of sound-signals under water. 



In the year 1826 M. Colladon made acoustical experiments in the Lake of 

 Geneva, which it is unnecessary to further describe, as a detailed account of 



