3i6 Transactions of the [Sess. 



tella were picked up. Several masses of Sponge [Halichondria) 

 were found growing in rock-pools, one of them very large, measur- 

 ing fully six inches by four inches, and two inches high. The egg- 

 capsules of both the Common Whelk and the Dog Whelk were 

 observed to be very abundant. A white membranous substance, 

 not known to any of those present, was found attached to a rock at 

 the bottom of a pool. It was shaped like an inverted bell-glass, 

 and measured not quite two inches in circumference, and three- 

 fourths of an inch deep ; it was very elastic in consistence. One 

 or two other specimens were afterwards observed. On being ex- 

 amined under the microscope, it was found to contain a mass of 

 eggs, and an attempt is being made to hatch these. I may here 

 incidentally remark that I made another visit to the same pools a 

 few days ago, and found one or two similar patches of eggs, and 

 sitting close beside one patch, apparently engaged in depositing 

 the eggs, I found the animal which I now exhibit — viz., a Doris, 

 one of the Nudibranchiata. Several specimens of the Sand-star 

 [Ophiura texturata) were found, and also one of the Polyzoa (Mem- 

 hranipora jnlosa), which we did not observe at Granton. 



No attention was given to Alga3 on this occasion, but it may be 

 incidentally mentioned that Joppa is one of the best stations for 

 Alga3 on the Firth of Forth. Mr G. W. Traill, Joppa, who is an 

 authority on this subject, records over 120 different Seaweeds as 

 having been found growing on the rocks or in the pools there. 

 Mr Traill has spent several years on this study, has carefully 

 noted the various periods of the year at which Algte are to be 

 found in fruit, and has in several other ways added to our know- 

 ledge on this subject. 



It may be worth while to say a few words as to the habitats of 

 some of the shell-fish we gathered. The Mussel and the Whelk are 

 to be found adhering to rocks between tide-marks — the former 

 anchored firmly to the rock by silken threads of great strength, 

 spun by means of its foot, and affixed to the rock and to its neigh- 

 bour Mussels. The Periwinkle is to be found either on rocks or 

 browsing on Algaj, such as Fucus ; while the Pearly-top is got 

 generally on the under side of tlie larger stones, in pools where the 

 water always remains. In searching for them, therefore, as well as 

 for many other marine objects, no stone should be left unturned ! 

 The Chiton is generally found adhering to rocks near low- water 

 mark, and when taken from its resting-place, rolls itself up after 

 the manner of a hedgehog. The Limpet was got of all sizes, and 

 adhering to rocks, some literally covered with Acorn-shells ; while 

 the Tortoise-shell Limpet, of which we secured only a few small 

 specimens, was got on the perpendicular sides of pools near low- 

 water mark. 



Marine botany and zoology, I would remark in conclusion, have 



