92 BULLETIN : MUSEUM OF COMPAKATIVE ZOOLOGY. 



DESCRIPTION OF PLATES. 



The Arabic numerals indicate the serial number of the vertebrae, the Roman 

 numerals the serial number of the ventral branch of the spinal nerves. 



ABBREVIATIONS. 



6r Nervus brachialis. il-h'ga. Nervus ileohypogastricus. 



cru. Nervus cruralis isch. Nervus ischiadicus. 



est. set. Sacral rib. prct. Transverse process. 



est. scr'. Supernumerary sacral rib. su'crae. Nervus supracoracoideus. 

 il. Ilium. 



All the diagrams are drawn to natural scale of a full grown individual, and 

 are viewed from ventral aspect. The size of nerves is drawn to scale roughly for 

 the average condition. 



