Holt and Calderwood — Report on the Rarer Fishes. 443 



mediterranea to that of Phycis mediterraneus or of a pale specimen of P. telescopium. 

 Both our Irish examples of the last-named species belong evidently to the pale 

 variety, and, except for the purplish ("gorge de pigeon," Valenciennes) hue on 

 the gill cover, are not unlike the darker specimens of Mora, but they are decidedly 

 darker than the smallest example. 



Anatomy. — On opening the abdominal cavity, the peritoneum is seen to be 

 of an intense opaque black ; and the general appearance of the viscera and 

 mesenteries is striking on account of their strong muscular character. (Plate 

 XLiv., A.) On examining the viscera a singular torsion towards the right side 

 is noticeable, so that several organs which usually occupy lateral positions are 

 found in the median plain. The amount of this displacement may be estimated 

 if we suppose that a cross-section of the abdominal cavity represents a circle 

 divided into four compartments, thus : X ; and if, after having filled in the viscera 

 of a Gradoid in the normal positions, we turn the subdividing lines on their axis, 

 the extent of one interval, or section of the cross, to the right-hand, imagining the 

 view of the viscera to be from the anterior aspect. The liver, for instance, has two 

 large lobes and one small central lobule. This central lobule, which, in ordinary 

 circumstances, may be seen in the ventral median line, occupies the right side ; 

 while the lobe of the right side occupies a dorsal median position, and the lobe of 

 the left side a ventral median position. In the same manner the reproductive 

 organs lie, not side by side, but are above the other, the organ which in ordinary 

 conditions would occupy the right side being in the dorsal position. The strong 

 mesenteries maintain this arrangement. Those in connexion with the repro- 

 ductive organs form a great sheath passing forwards on the dorsal surface of the 

 stomach, below the dorsal lobe of liver, a branch bending round the left side of 

 the stomach to support the ventral lobe of the liver. The dorsal lobe of liver is 

 the longest, and extends backwards about two-thirds of the abdominal cavity. 

 The stomach is large, with a wall of great muscular thickness, especially on the 

 dorsal aspect. In the specimen under examination, the wall, at its thickest, 

 measured 1| inches. The torsion, already referred to, causes the duodenum to 

 spring from the right side. The lumen is narrow, and the intestine, after 

 making two simple bends so as to form a long, much flattened S, passes to the 

 anus. There are twenty pyloric ceeca, which bend laterally and posteriorly, 

 encircling, to a certain extent, the ventral lobe of liver. 



The swimming bladder exhibits a condition of great interest. A lateral view 

 of the organ, after the removal of its right side, is seen in Plate xliv., A. It 

 consists of two primary portions : the larger situated partly above and partly 

 posterior to the abdominal cavity ; the smaller situated in front of this, partly 

 above the thoracic region, and partly in the region of the head. Those two 

 portions are in communication with one another by means of a canal sunk into 



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