174 



DR. C. F. SONN'fAG ON THE 



The left vagus ami phrenic nerves are fused in the anterior 

 parb of the thorax, there being only superficial furrows to mark 

 the distinction between them (text-fig. 15, A). 



The lungs have large alveoli, as shewn by John Hunter (12). 



Text-figure 15. 



PA. 



A : The adhesion of the left vagus (v) and phrenic (p) nerves. 



B : The aortic arch (a.a.) giving off innominate (ia.), left subclavian (l.s.a.) and three 

 intercostal (1a, 1, 2, 3) arteries; la., ligamentum arteriosuin ; pa. and LPA., 

 pulmonary and left pulmonary arteries. 



The Generative Organs. 



The internal generative organs of the female have been 

 described by John Hunter (12), Klinckowstrom (6), and 

 Rapp (10). Those of my specimen were not examined, for 

 the gravid uterus was at once removed for embryological research. 



The external genitalia and anus are all enclosed in a species of 

 cloaca, and the clitoris is a small semicircular flap. The male 

 organs also exhibit a primitive condition, and John Hunter (12) 

 has described them as follows: — " The penis is a short flat body 

 enclosed in a prepuce which is within the verge of the anus. It 

 is not above two tenths of an inch in length, and terminates in 

 an obtuse point. It has a groove which runs along the under 

 surface, and which makes the point somewhat forked." 



No os penis is present. 



Ballowitz (15) has described the spermatozoa. 



The Pelvic Bones. 



The skeleton of the specimen, described above was recently 

 obtained by me from Mr. Gerard, and the pelvis was compared 

 with that of a male animal which was preserved in the Society's 

 Prosectorium. There are numerous and striking differences be- 

 tween them; these are seen in the measurements of the different 



