44 



SCIENCE, 



[Vol. IV., No. 75. 



rock-sections directly with the microscope, with very 

 satisfactory results. It is hoped to use this method, 

 of preparing plates for publication, to be reproduced 

 by some heliotype or autotype method. Mr. Merriam 

 took the field the latter part of May in south-eastern 

 Dakota, where he proposes to study the quartzites ex- 

 posed at a number of places between the James Elver 

 and the Minnesota state line. 



Mr. Vanhise, during May, continued his micro- 

 scopic work, having prepared some forty new written, 

 descriptions of greenstones, chiefly from the original 

 Huronian of the north shore of Lake Huron. The 

 microscopic as well as field study of this formation 

 has been found necessary, as it forms the type with 

 which the rocks of all the other so-called Huronian 

 areas must be compared. 



Mr. Vanhise has also prepared a number of new 

 sections, including some additional ones of the sand- 

 stones which he has described in his paper on secon- 

 dary enlargements of felspar fragments published 

 in the American journal of science for May. The 

 new sections show the enlargements even more dis- 

 tinctly than the ones previously described by him, 



and leave no room for doubt as to the correctness of 

 this very important observation. Mr. Vanhise will 

 probably take the field in north-western Michigan in 

 the agogebic belt of Huronian schists. 



Unalashka sands. — Mr. J. S. Diller's report on the 

 Unalashka sands will be published by the U. S. signal- 

 office, and the geological survey has promised to ex- 

 amine and report upon any other volcanic sands or 

 atmospheric dusts that may be collected by that 

 bureau. Their observers, especially on Mount Wash- 

 ington and Pike's Peak and in Alaska, have been in- 

 structed to collect and preserve any sands or dusts 

 that may fall, or be brought down from the air by 

 rainfall. 



Artesian wells. — Prof. T. C. Chamberlin has pre- 

 pared a paper on artesian wells for the fifth annual 

 report of the survey. 



Dr. Peale has reports from Montana that work has 

 been resumed on the artesian wells at Helena and at 

 Billings, and that the second boring at Miles City, on 

 the Yellowstone, reached flowing water at a depth of 

 four hundred and fifty feet, which is a hundred feet 

 deeper than in the first well. 



RECENT PROCEEDINGS OF SCIENTIFIC SOCIETIES. 



Cincinnati society of natural history. 



July 1. — Dr. Walter A. Dun read a paper on the 

 recent floods in the Ohio valley. He tabulated the 

 measurements of all the floods since 1832 of which 

 we have trustworthy records. The river has reached 

 the height of fifty feet and over, fourteen times since 

 1832. All of these floods except one (that of August, 

 1875), have occurred in the winter months, and seven 

 in the month of February. The extremely high water 

 is the result of a long-continued and widely extended 

 rainfall upon an accumulation of ice and snow, or 

 upon the frozen ground. These conditions are suffi- 

 cient to account for floods, not considering the ques- 

 tion of the reduction of timber areas. Mr. Charles 



Dury, in a brief paper, described the finding, for the 

 first time in our locality, of Adranes LeContei, a beetle 

 inhabiting ants' nests. This beetle is kept by the ants 



for the honey-like secretion which it exudes. Mr. 



Joseph F. James stated that a recent discovery in 

 the lower Silurian rocks of Clark county, O., makes 

 it clear that some of the so-called ' fucoids ' are un- 

 doubtedly caused by the oscillation of crinoid stems 

 over the soft mud. 



Brooklyn entomological society. 



June 29. — Mr. J. B. Smith read a paper on some 

 structural modifications of the Noctuidae with refer- 

 ence to their geographical distribution. Three typi- 

 cal faunae inhabit America north of Mexico; the 

 northern of which, the Labrador fauna, is typical ; the 

 eastern agreeing in all essential characteristics with 

 that of central Europe; and the western, peculiar to 

 this country, reaching to the Pacific, thrusting long 



extensions into the southern states, and small spurs 

 into the middle states. The northern fauna is typi- 

 cally represented by Anarta and the Pachnobia group 

 of Agrotis, and is characterized by small head, smooth 

 clypeus, often narrow ovate eyes, plump figure, and 

 long, hairy vestiture. The northern species of Plusia, 

 of which P. Hochenwarthi maybe considered typical, 

 share this tendency to ovate eyes, and, having also the 

 tibiae spinose, must receive separate generic designa- 

 tion. Caloplusia is proposed to designate these forms, 

 which usually also have the secondaries yellow. This 

 northern fauna is indicated again in the high north- 

 west, and is traceable in the mountainous regions of 

 northern New York and the New-England states. 

 The eastern fauna is characterized by more propor- 

 tionate head, the front usually smooth, the body ves- 

 titure scaly, usually overlaid or intermixed with hair. 

 The tibiae, when armed, are usually all of normal 

 length; and the armature consists of spines. The 

 maculation is normally noctuidous, and the wings are 

 ample. The western fauna is most peculiar. The 

 front is strongly modified, tuberculate, rugose, or exca- 

 vate: the tibiae are heavily spinose, the anterior pair 

 often shortened, and the armature consisting of long, 

 corneous, claw-like processes. The 9 oviduct is also 

 more or less prominently extruded. As a whole, the 

 heliothid type prevails ; and even Agrotis takes a dis- 

 tinct heliothid tendency in the tuberculate front and 

 heavily armed fore-tibia of the western species. Be- 

 longing to no special locality, but perhaps more dis- 

 tinctly south-western, is that group of which Phurys 

 and Syneda are typical, and which agrees in distribu- 

 tion with the Tenebrionidae among the Coleoptera. 

 The speaker asked, What is the peculiar circumstance 



