83 



back, the second, excepting the first pair of ganglia, in the 

 front of the body : 2d, the spinal chord never forms a ring 

 through which the oesophagus passes, but the ganglionic chain 

 always does: 3d, the ''vesicular substance" of the spinal 

 chord is continuous throughout, and never intercepted, as it is 

 in the ganglionic chain of the Invertebrates. It may be laid 

 down as a general proposition, that the organs of animal life, 

 that is, organs of the motory or sensorial systems are never 

 homologous in the different great divisions of the animal king- 

 dom. Parts may be analogous.^ have similar functions, as the 

 wing of a bird and the wing of an insect; but they are not 

 identical parts. 



The enlargements of the spinal chord have been noticed in 

 many Vertebrates, though they do not exist so distinctly as Gall 

 and Spurzheim have described. Their existence is interesting 

 as tending to show that the spinal axis, as regards its typical 

 structure, like the muscular, the osseous, and the vascular sys- 

 tem, is reducible to a linear series of segments, which are equally 

 repeated in the length of the body. 



Prof. Wyman also exhibited the cranium of a Flathead 

 Indian, from the Columbia River, which had been recently 

 presented to him by Dr. H. C. Perkins, of Newburyport. 



It exhibited in a marked degree the distortion from pressure 

 during infancy, by which the members of many of the tribes in 

 Oregon are characterized. The distortion consists in a depres- 

 sion and an indentation of the forehead ; the upper and middle 

 part of the face being thrust back so that the orbits are directed 

 a little upwards ; the crown of the head is likewise depressed, 

 and the parietal bones are bent upon themselves so as to form an 

 acute angle, which, in place of the occiput as in the natural con- 

 formation, constitutes the most posterior pai't of the head. The 

 breadth of the head and face is very much increased. The 

 right and left half of the cranium are not symmetrical, the right 

 being much the most compressed. In the neighborhood of the 

 left ear the cranial walls are much dilated, from unequal press- 

 ure, so that the mastoid process of that side is completely lost 

 and its substance is apparently converted into the immediate walls 



