PROVISIONAL REPORTS AND NOTICES. 391 



facts recorded in these papers were the following : — Rolled specimens of Pur- 

 pura lapillus, a shell which lives only above low-water mark, were found in 

 twenty-eight to thirty fathoms water on the gravelly bed of a line of current 

 at the distance of eight miles from the nearest shore. In the same line of 

 current it was found that the few mollusca which lived there, such as ModiolcB 

 and LimcB, had constructed nests or protecting cases of pebbles bound to- 

 gether by threads of byssus ; and one species, the Modiola discrepans, had 

 made its nest of the leaf-like expansions of Flustrafoliacea cemented together. 



The attention of the dredgers was directed among other subjects to the 

 distribution of Serpulce, and the results of their researches were confirmatory 

 of the statements recently advanced by Dr. Philippi of Cassel, namely, that 

 no dependence could be placed even as to the genus on the shell of a Ser- 

 pula, perfectly similar shells being constructed by animals of different genera. 

 Thus they found all the Serpulce of a particular form in twelve fathoms water 

 to be a species oi Eupomatus, whilst exactly similar shells in twenty fathoms 

 proved to be the habitation of a species of the genus, wanting opercula, of 

 which Serpida tuhularia is the type. All the triangular Serpulce they met 

 with were Pomatoceros tricuspis. In twelve fathoms, at the entrance of the 

 Menai Straits, they dredged the shell of Helix aspersa, the common snail, 

 covered with barnacles and Serpulce, and inhabited by a hermit crab. 



The second part consisted of a series of dredging observations on the Irish 

 coast, drawn up by Mr. Hyndman. 



On the Hourly Meteorological Observations carried on at Inverness, at 

 the Expense of the British Association, by Mr. Thomas Mackenzie, a 

 Provisional Report was presented by Sir D. Brewster. 



On the Forms of Ships. 



Mr. Scott Russell reported that the Committee on the form of ships 

 had now completed their labours ; that the whole of the tables of the experi- 

 ments and all the drawings of the forms of the ships were now ready for pub- 

 lication. These tables were so voluminous, and the plates required for illus- 

 tration were so numerous and expensive, that the question of publication was 

 likely to be attended with some difficulty ; but a committee, consisting of the 

 President of the Royal Society, the Dean of Ely, Colonel Sabine and Mr. 

 Taylor, had been appointed for the purpose of making the necessary arrange- 

 ments. He had now to communicate to the meeting an important addition 

 which had been made to these experiments during the past year. The mem- 

 bers of this Section were aware that the former experiments made by the 

 Committee comprehended vessels of many forms and various sizes, from the 

 length of a few inches to ships of 2000 tons displacement ; but in all these 

 experiments direct mechanical means of propulsion had been employed and 

 not the force of the wind, and they were therefore regarded as applicable to 

 steam-vessels rather than to sailing ships. During last year, however, most 

 satisfactory experiments had been made in which the propelling force was the 

 wind acting on the sails of the vessel of the open sea. The circumstances in 

 which this experiment originated displayed in a striking manner the advan- 

 tages conferred by an Association like this on the districts which it visited. 

 The two gentlemen who had conducted this experiment were both Irishmen, — 

 one. Dr. Corrigan of Dublin, having become acquainted through the last meet- 

 ing in Cork with the experiments of this Association, determined, in building 

 a pleasure-boat, to carry out the principles which had been established by 

 those experiments, and to have his vessel built on that form which was pointed 

 out by these experiments as the^rw* of least resistance ; he accordingly built 



