56 



Part III. — Twenty-eighth Animal Report 



The post-clavicle is a bone which varies much, and at first sight its 

 representative in the Lochtyne specimen gave room for doubt, but it, I found, 

 agreed also with its counterpart in other cod. 



Although the fish was a little misshapen, I do not think it was other than 

 a normal Gadus callarias. 



Stone in the Bladder of a Cod. 



Mr. M'Lachlan also forwarded an urinary bladder of a cod which contained 

 a large stone. 



The roe, with the urinary bladder attached, is shown reduced in fig. 13. 

 The roe, which was ripening, measured 4| inches in greatest length. The 

 urinary bladder consists of two lobes, one which is practically of normal size 

 (lo.), and the other very much enlarged (lo ] ). The latter contained a large 

 stone, which is shown in natural size in fig. 17. The ureter (ur.) had been 

 cut away. The drawing of a normal urinary bladder (ur. bl.) is provided in 

 fig. 18. It is made to the same scale as fig. 13. Dr. Milne, University 

 College, Dundee, informs me that in its chemical composition the stone 

 resembles the urinary calculus of the human subject. 



Several smaller calculi were found in the interior of a cod at Aberdeen. 

 They had evidently been in the urinary bladder. The largest was about 

 |-inch in diameter. They were not perfectly spherical. 



Cod Bitten by a Cephalopod Mollusc? (Figs. 29 and 34.) 



Two prominent scars (scr.) were found on the shoulder of a large cod. 



In the fresh condition the scars had a greenish colour. They appear to 

 have been due to the bites of cuttlefish (Loligo or Octopus), as described by 

 M'Intosh.* The part had been preserved in formaline before examination. 



The sores have filled up with tissue consisting of fascia and muscle. 

 The ends of two ribs (r., fig. 94, shown in dotied lines) are tightly bound to 

 the posterior scar, while the anterior scar has below it the head of the post- 

 clavicle (pt. cl., ib.), which has been exposed apparently by the excision of 

 a portion of the clavicle. The head of the post-clavicle is normally covered 

 by the clavicle. 



A section through the larger scar is shown in fig. 29. This scar has a 

 distinct rim or margin (rm., figs. 29 and 34). The epidermis is absent from 

 the uninjured skin, having evidently been rubbed off. The section shows to 

 the right the normal derma (d.), containing the scale-pits (scp.), and having 

 its outer layer pigmented (p.). The pigmented layer ends ac the edge of 

 the scar. On the surface of the scar there is a soft layer of dead tissue (d.t.), 

 greenish in colour. Beneath it is seen the live tissue, which is also stained 

 a pale green. The scar has been healed by the lateral outgrowth of the 

 tough white derma. It forms the broad rim {rm,). The part of the scar 

 within the rim, and next to it, is formed by the great development of the 

 lighter layer of fascia (f.) below the derma, which has accompanied the latter 

 in its outgrowth. The central part of the wound (c.) is occupied by a pad 

 consisting in its outer rind of fascia and fibres tightly bound together. It 

 forms a protective layer which is not sharply separated off from the muscles 

 beneath. In parts the cortex can be split longitudinally in the same sense 

 as the run of the muscle-bundles ; in other parts the rind will not split 

 readily. 



An encysted parasite was embedded in the scar. It resembled much the 

 trematode cysts found in the skin of the whiting (Gadus me'langus). Vide 



* (1) "Injuries to Baited Hooks and to Fishes on the Lines." Fourth Annual 

 Report of the Fishery Board for Scotland for 1885, p. 203. 1886. 



(2) "Further Remarks on Injuries to Food-Fishes on the Lines." Tenth Annua/ 



Report of the Fishery Board for Scotland for 1891, Pt. III., p. 299. 1892, 



