CLELAND ON THE ANATOMY OF THE SHOUT SFN-ETSH. 185' 



arrangcniciit of fibres, mentioned in the text. The manner in which tlie crj'stals 

 lie in the tubes is exhibited. 



Plate VI — Fig. 1. Skeleton of the head and shoulder, a, supraoccipital bone ; 

 h, paroccipital ; e, fi-ontal ; d, nasal ; e, prefrontal ; ./', bone of the interorbital 

 septum; r/, orbitosphcnoid ; /, alisiihenoid ; li, postfrontal ; /, mastoid ; wj, scapula ; 

 n, coracoid; o, ulna; j), the bone described ui the text as belonging to the row of 

 cari)al bones, yet corresponding to the radius in its relations to the coracoid and 

 idna ; q, the bone called clavicle ; r, intermaxillaiy ; s, maxillary ; t, palatal ; 

 V, dental, articular, and angular portions of the lower jaw; w, entopterygoid ; 

 x^ hy]iotympanic ; y, mesotym])anic ; z, epitympanic ; 1, operculum ; 2, prcoper- 

 culum, beyond whose posterior and anterior margins are seen projecting the 

 intero]>erculum and suboperculum. 



Fig. 2. View of the muscles a, muscles of dorsal fin ; h, muscles of anal 

 fin; c,c, are placed opposite the most su]ierior and most inferior muscles of the 

 caudal fin; rl, small abdominal muscle, arising from the tip of the clavicle, and 

 resting on the jieritoneum; e, the other small abdominal muscle, arising from the 

 ulna, and likewise resting on the peritoneum. The peritoneum is torn open 

 inferiorly, so as to exhibit the inferior margin of the liver, and the intestines sur- 

 rounded by their common investment, together with, y, the peritoneal ligament con- 

 necting the liver and intestines; rj, the vent. 



Fig. 3. A few of the individual muscles of the left side of the anal fin, showing 

 how each muscle is sheathed by that in front, and how the tendons pass into the 

 grooves, and are there invested with sheaths. 



XVIII.— On the Structure and Composition of the Integu- 

 ment OF the Oetheagoriscus mola. By William Turner, 

 M.B. (LoncL), r.E..S.E., Senior Demonstrator of Anatomy, 

 University of Edinburgh. 



Seteral noteworthy peculiarities, both structural and chemical, 

 are presented hy the integument of the short sun-fish. These I had 

 an opportunity of examining, not only in the specimen dissected by 

 Dr. Cleland, but in one dissected a few years ago by Professor 

 Goodsir and myself The skin of the latter varied in its thickness 

 in different parts of the body of the animal, from not more than a 

 quarter of an inch to four or five inches. In one examined many 

 years ago by Mr. Groodsir, which was a remarkably large fish, it 

 reached in places as much as six inches.* The great thickness of the 

 slun was produced by an opaque, white, tough and resisting structm-e, 

 which extended from the tubercle-covered surface of the integument 

 to the loose areolar tissue lying between it and the muscles. WTien 

 blocks of this white structure were cut off, and set on one side for a 

 short time, a considerable quantity of a pale straw-coloured, serous- 

 looking fluid drained off" from them, so as greatly to diminish their 



* In the Edinburgh Philosophical Journal, vol. 30, p. 188, Mr. Goodsir gives an 

 account of the microscopic characters of the skin of this specimen, which he dis.se<t3d 

 in 1840. but as he only employed a doublet in the examination, the description is 

 necessarily an imperfect one. 



N. H. R,— 1862. O 



