Editorial Miscellany. . 95 



American Indians. Although familiar with this mound from my boy- 

 hood days, when I would gaze on it with Avonder not unmixed with 

 awe— standing there all alone among the wild hills, the imperishable 

 record of a dead and forgotten race — it never occurred to me to 

 examine it with any accuracy, until last May, while on a visit to my 

 father, and then I could only give the time to a surface survey. But 

 it is my intention to visit that country again, between this and the 

 coming spring, and institute a careful exploration, and if I should find 

 anything of value to the inquiry into the habits and history of the long 

 perished races on this continent, it will be a pleasure to me to confer 

 with you, and submit the results to your consideration. 



— MoLLUscA. — W. W. Calkins, of Chicago, in a recent communica- 

 tion, states, that since the publication of his paper on " Land and 

 Freshwater Shells of LaSalle county, Illinois," in a previous number of 

 this Journal, he has identified the following species in addition to the 

 one hundred and five enumerated in his catalogue : Unio parviis — 

 (Barnes) ; H. imlehella — (Muller) ; and H. costata — (Muller), said to 

 be a strongly ribbed variety of H. pidchella, and Ancylus tardus — 

 (Say), which sj^ecies he found in the Vermillion river, clinging to 

 small stones. The variety costata are very distinctly marked. He 

 observes that they have been found in other sections, and follows 

 Binney in placing them as above. 



— Meteorology. — The following interesting summary of observa- 

 tions of atmospheric phenomena, obtained from the Signal Service ob- 

 server at this point, should be read by all who would converse intelli- 

 gently upon that all-absorbing topic — " the weather:" 



The Atmosphere. — The circulation of the atmosphere around the 

 earth bears a striking analogy to the waves of the ocean, except that 

 the atmospheric waves are of vastly greater dimensions. It extends in 

 height to the point where the two forces arising from the earth's rota- 

 tion and the earth's attraction are about equal. The vapor of water 

 contained in the atmosphere is the prime influence disturbing its 

 equilibrium. This vapor absorbs heat and renders the air Hght, caus- 

 ing it to ascend. The earth's surface absorbing the greater portion of 

 the sun's rays, the air is heated principally at the bottom, when it as- 

 cends and loses its heat by radiation most rapidly at the top. As this 

 light, moist air ascends into the upper regions, where the temperature 

 gradually becomes lower, the vapor of water of which it is largely com- 

 posed condenses, and when the upward cm-rents have no longer power 

 sufficient to uphold this aqueous accumulation, it is precipitated in the 



