1)K JOHNSTON ON THE CEPHALOPODA OF BBRWICKSH1KK. 197 



found together, and the great similarity between the Balanus clothed 

 with its first shell and the animal in question, tend very strongly to con- 

 firm Mr Thompson's observations. It seems to me highly probable that, 

 previous to the decisive change, the animal turns half round in its case 

 BO as to be nearly at right angles to its former position. 



The organ by which the young animal fixes itself is the fore-foot ; this 

 part, therefore, is liable to be injured in detaching it ; and this may be 

 the reason why I only saw one fore-leg, though Mr Thompson gives 

 two in his figure. 



May and June seem to be the months when the young Balani are 

 most numerous. Those who wish to observe the singular transforma- 

 tion should be on the watch at that time ; and it is certainly very desi- 

 rable to obtain as many and as complete observations as possible on such 

 an interesting subject of inquiry. 



A description of the CEPHALOPODA which inhabit the coast of 

 Berwickshire. By Dr JOHNSTON. 



CEPHALOPODA DIBRANCHIATA. 



* Head surrounded with eight nearly equal arms. 



1. OCTOPUS. Body enclosed in a sub-globular sac, rounded at the 

 base, unfurnished with fins ; arras connected at their origins by a 

 broad membrane ; suckers sessile, toothless. 



** Head surrounded with eight arms and two long tentacula. 



2. LOLIGO. Body enclosed in an elongated cylindraceous sac, pointed 

 at the base, and winged below, separate behind from the neck ; 

 suckers pedunculate, the riin strengthened with a horny denticulated 

 ring ; dorsal plate thin and horny. 



3. SEPIOLA. Body enclosed in a short sac, rounded at the base, furnished 

 with rounded fins attached to the sides ; dorsal plate horny, minute 

 and very slender. 



4. SEPIA. Body enclosed in an oval sac rounded at the base, fur- 

 nished on each side throughout its whole length with a narrow fin, 

 and strengthened dorsally with a calcareous lamellated cellular oval 

 plate, lodged in a peculiar cavity ; suckers irregularly scattered, 

 with horny toothless margins. 



I. OCTOPUS. LAMAKCK. 



1. O. ventricostts, scentless ; body ovate, smooth or granular, proft. 

 sprinkled with reddish-brown dots ; arms straight, taper, longer than 



