1884.] 163 [Hyatt. 



izecl forms which are strictly progressive, show a certain stability 

 and uniformity of characteristics, a less noticeable tendency to va- 

 riation, which is a result of their fitness for the narrower fields and 

 habitats in which they exist. It is, therefore, illogical to argue 

 from investigations upon them, that a corresponding uniformity 

 existed in their ancestors. 



The great mass of life, as shown by the fossils, has been pro- 

 gressive, and the progress was similar to that of the individual 

 from a more generalized to more and more specialized conditions 

 and structures. The primitive stocks like the primitive Metazoa, 

 the Porifera, were certainly much more variable and unstable than 

 the later and more complicated forms which are more stable and 

 less susceptible of change. Thus when radical changes become 

 necessary in order to sustain the life of the species of a group, they 

 die out as did the Ammonites, or decay as did the Nautiloids, and 

 exhibit most clearly the stability they have acquired as progressive 

 forms in their inability to meet the requirements of different modern 

 conditions. 



This law of progress in structure is precisely parallel to Dr. M. 

 E. Wadsworth's law of the evolution of chemical compounds on the 

 earth's surface, and forms a supplement to his hypothesis of the 

 progress of inorganic substances from unstable to more and more 

 stable combinations, and his researches first suggested the idea we 

 have given above. 



In conclusion we desire as a personal matter to state, that as it 

 proved impossible to illustrate this paper, the author, being about 

 to enter upon a long series of researches of a very different na- 

 ture from those given above, was obliged to take advantage of 

 the present opportunity of publication, or resign altogether the 

 idea of making his work in this direction useful outside of the class 

 room. 



Dr. M. E. Wadsworth read a paper on the evidence that the 

 earth's interior is solid. (See Amer. Naturalist xviii, 587 et seq.) 

 The following letter from Dr. S. Kneeland was read : 



Apropos of the "Sea Serpents," alluded to at the meeting of Jan. 2, 

 I will relate my experience with some water snakes which I caught in 

 Manila bay in November, 1881, while undergoing a quarantine of three 

 days. We were anchored about three miles from land, in water twenty 



