A Contribution to the Anatomy of Siren lacertlna. 



By 

 Harris H. Wilder, Ph. Dr., 



Assistent in the Anatomical Institute of the University of Freiburg i. B. 



(Aus dem Anatomischen Institute zu Freiburg i. B.) 



With plates XXXIX— XL. 



Introduction. 



Some months ago it was suggested me by my teacher, Prof. Wieders- 

 HEiM, to investigate the nose of Siren lacertina; the form of the nasal 

 capsule, its relation to the skull, and the disposal of the mucous mem- 

 brane within it. While preparing this part, I was led to the study 

 of the cranial nerves, and through these, the muscles of the head. 

 Although the anatomy of this animal has already been treated at 

 some length, yet little or none of it has been written since the days 

 of modern microscopical methods, the employment of serial sections 

 and the like. Having, therefore, far better means at my hand than 

 had the earlier investigators, I have been able in many cases to 

 complete partial investigations or to study new ground, while in others 

 I have obtained results differing from the previous ones. 



I have endeavored, especially in the first three sections, to de- 

 scribe quite fully the method of dissection, which I have found the 

 most practical for the demonstration of the difierent parts, thus making 

 the work serve also as a laboratory handbook, which may be used 

 in general Urodelan dissection. 



I will here take the opportunity to express my warmest thanks 

 to my teacher. Prof. Wiedersheim, for the personal and friendly 

 interest which he has taken in me and my work from the beginning, 

 and for the abundance of excellent material which he has furnished 

 me for the work. I wish also in the name of Prof. Wiedersheim, to 

 thank the Smithsonian National Museum in Washington, from which he 

 obtained the greater part of the material which he placed at my disposal. 



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