A Contribution to the Anatomy of Siren lacertina. ßj^3 



Ausdehnung der Nasenkapsel nur mit punktirten Linien angegeben, 

 und zwar finden sich zwei Reihen derselben im hinteren Bereiche, um 

 damit anzudeuten, dass ich über die Anheftung der hinteren Circumferenz 

 des Riechsackes nicht ins Klare gekommen bin. Es mögen dies Andere 

 sicherstellen" (P. 28). 



The task which he suggested in these last words, I have here 

 undertaken, using the following methods for my investigations. 



I first attempted several macroscopic preparations, which, however, 

 owing to the intimate adhesion of the skin and connective tissue to 

 the capsule, gave only a partial success. 1 then prepared a series of 

 microscopic sections from which I made several reconstructions on 

 checked paper by means of measurements with a micrometer eye-piece, 

 drawing the capsule from several aspects. Finally I constructed an 

 enlarged card board model from the sections. From the results obtained 

 by these several methods, which were quite in accord with each other, 

 I constructed the drawing used in the somewhat diagrammatic figure 11, 

 which represents the entire nasal region as seen from above. In this, 

 the capsule of the right side is drawn free from the other parts, but 

 in its proper relative position, while on the left its relations to the 

 skull are shown. The aspect of the capsule from the external side 

 is given in the figure of the cranial nerves. 



Shape. The capsule is irregularly oval in shape, with a long 

 narrow process extending directly backward, and a lateral posterior 

 wing. In a general way it may be said to form the roof of the nose 

 only, although at the front and in places along the sides it is curved 

 downward and a little inward. An inferior process runs outward from 

 the anterior exterior corner, curving around the anterior nasal aperture 

 and projecting laterally a little farther than the capsule itself. The 

 anterior nasal aperture is thus nearly surrounded by cartilage. At 

 the anterior inner corner the cartilage forms a sheath for the R. oph- 

 thalmicus profundlis, which issues from it. Above, the central 

 portion of the capsule fails, leaving an irregular opening which is 

 filled in by connective tissue. There is a small foramen in the lateral 

 wing, through which runs the N. n a salis ex ter nus. 



Relation to the skull. The nasal cartilages lie on either 

 side of the anterior rostrum of the skull, their inner edges being ad- 

 jacent to the praemaxillary, frontal and ethmoid bones. The last- 

 named bone completely surrounds the posterior process of the capsule, 

 this being demonstrable only by sections. The cartilaginous internasal 

 septum lies between and just inferior to the capsules of the two 



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