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Part III. — Seventh Annual Report 



tion could have commanded success in a situation presenting great natural 

 difficulties to the rearing of mature mussels. The success of mussel culti- 

 vation at Montrose is all the more apparent when it is contrasted with 

 other places in Scotland where the conditions are much more favourable, 

 and only ruined beds are found. Nature has not been so bountiful to 

 Montrose as it has been to the Clyde, the Tay, and some of the northern 

 firths, yet the obstacles have been in a measure overcome notwithstanding 

 the prolonged time taken by the Montrose mussels to fatten, and the small 

 size, two inches, to which they grow even after three to five years tending. 



The lagoon has a comparatively narrow outlet to the sea by the River 

 Southesk, and is formed on the east side by Rossie Island, and a barrier of 

 boulders (on which the present town of Montrose is built) ; this barrier is 

 flanked on the seaward side by an accumulation of blown sand constituting 

 the links. The River Southesk as it leaves the basin divides into two — 

 the Inch Burn on the south, and the main stream on the north, which forms 

 the harbour. Between these two streams lies the island of Rossie, which 

 at low water is practically part of the south bank, the Inch Burn becoming 

 dry or nearly so. The island of Rossie is connected to the town of Montrose 

 by a suspension bridge, between which and the sea, the dredging by the 

 ' seed gatherers ' is done. On the northward shore a great thickness of 

 blown or stratified sand overlies a bed of clay, the outcrop of which is 

 seen at one or two places, and reveals considerable quantities of shells. 

 These are enclosed in situ, and comprise Scrobicularia piiierata, Bellon ; 

 Cardium edule, L. (the common cockle) ; Mytilas edulis, L. (the common 

 mussel); Tellinabalthica,'L.; Littorina litorea, L. (whelk) ; Hydrobia ulvce, 

 Penn., all of which are littoral or shallow water forms, and were obtained 

 by us in the Scrobicularia clay. They are also recorded as living forms in 

 the present basin.* This Scrobicularia bed is well developed on the south 

 side of the basin, and Dr Howden in his paper on the geology of the super- 

 ficial deposits at the estuary of the Southesk, chronicles its occurrence 

 higher up the estuary at Balwyllo, below the Free Church at Maryton, and 

 below the Parish School. The occurrence of this shell-bearing clay at the 

 places mentioned, indicates, if proof w r ere wanted, that the estuary of the 

 Southesk occupied a much larger area than it does now, and Dr Howden's 

 opinion is that the tidal-basin extended up as far as the farm of Kincraig, 

 a mile below Brechin. 



II. Method of Cultivation. 



The mussels with ripe reproductive organs are found on the estuarine 

 flats of the basin, or on the sloping surface of the Inch Burn. The 

 genital glands of the common mussel are known to be sexually ripe 

 in certain localities in the spring months. Mr Johnston is of opinion 

 that the mussels of Montrose spat in May, June, August, and the 

 beginning of September, while others hold that the mussel spats 

 all through the year. The liberated embryos, which are carried sea- 

 wards by the quickly running tide, obtain a foothold on the shores of 

 Rossie Island, on the Scalp, on the Binny Bank, on the north and south 

 shores of the Esk from the suspension bridge downwards, and. in the bed 

 of the river. From the swiftness of the current only a very small amount 

 of the spat obtains a resting-place in the Southesk, the bulk of it being 

 carried out to sea. But wherever there are sheltered spots — where there 

 are eddies and slowly running back-currents — there, the young mussel 

 may obtain a resting-place. A glance at the map, with its serpentine lines 

 indicating the position of the ' seed ' beds, illustrates this. The outgoing 



* Trans. Edin. Geol. Soc, vol. i. p. 138. 



