112 



SCIENCE. 



LYol. IV., No. 79. 



this insect swarmed in such numbers as to cover 

 every exposed surface, and literally to darken the 

 air to a height of fifty to seventy-five feet. When 

 the Ephemerae emerge from the water, their flight 

 is weak and uncertain. Instinct teaches them that 

 they are carrying an extra armor, and they seek at 

 once the nearest support as a place on which to 

 moult. At such times these insects are as easily dis- 

 turbed as a swarm of bees. A gust of wind from an 

 unexpected quarter, giving a slight rustle to the 

 leaves, will often cause them to rise in clouds from 

 each branch. This motion seems a circling one; but 

 the appearance is probably due to the fact that many 

 of the insects are moving back upon the branches, 

 while others are still ascending. No other insects 

 were at all common along the lake during this time. 

 It may be worth placing on record that that vener- 

 able citizen known as the oldest inhabitant was 

 speechless in the presence of these swarming millions. 

 His memory could not recall another year in which 

 the numbers were worthy to be compared with those 

 of 1884. It will be impossible to convey in words an 

 adequate conception of this invasion to those who 

 have never witnessed any thing of the kind. 



Near the dock at Lakeside there is an electric 

 lamp suspended about twenty feet above the ground. 

 As might be expected, this became an object for at- 

 tack as soon as the current was turned on in the 

 evening. On the morning of July 7 the layer of 

 dead insects covered an area of not less than twenty- 

 five square feet, and was fully six inches deep imme- 

 diately/ underneath the lump. Kelley's Island, four 

 miles distant, appeared all the while as if enveloped 

 in such a cloud of dust as rises over a race-course. 

 On the evening of July 6 a wind compelled the 

 insects to fly very close to the surface of the water, 

 and their numbers appeared fully as great as the 

 snowflakes of a winter's storm. During these ten 

 days the invasion extended along the entire south- 

 ern shore of the lake, from Buffalo, through Cleve- 

 land, Sandusky City, and Toledo, to Detroit. After 

 a rain-storm the water of the lake was dense with 

 them to a depth of at least two feet. Along the 

 beach they were gathered in windrows. As far as 

 my observation goes, fish will not eat the dead in- 

 sects, but greedily devour living ones. The min- 

 nows are very expert at this work, rarely failing to 

 make a capture if the insect has touched the water. 



According to Packard, all the Ephmeridae pair 

 while on the upper surface of the water. This is not 

 strictly correct, for any afternoon one could see thou- 

 sands of couples flying in the air and at elevations 

 as great as fifty feet. When this took place over the 

 water, the couple almost invariably fell into the lake, 

 and was devoured by the fishes. Is nature produ- 

 cing a stronger-winged variety ? 



Edward T. Nelson. 



Ohio Wesleyan university, 

 Delaware, O., July 28. 



[The phenomena seen by Professor Nelson, as de- 

 scribed by him, appear to be different from those wit- 

 nessed by Kev. Mr. Abbott, and in all probability 

 a wholly different insect was concerned. The myri- 

 ads of Ephemeridae mentioned by both writers have 

 been not unfrequently witnessed. A woodcut of a 

 street-lamp in Cleveland, swarming with Ephemeri- 

 dae, will be found in Morse's ' First book of zoology.' 

 We have ourselves seen, from a long distance, wind- 

 rows of their dead bodies and exuviae along the 

 shore of Lake Winnipeg for very many miles, while 

 the water of the lake was so covered with them 

 that one could not dip up a cup of clear water. — Ed.] 



Man and the mastodon. 



Having had occasion recently to look over num- 

 bers of the American journal of science of forty years 

 ago, I have met with several notices of archeological 

 interest. Among them is the following, in an article 

 on the suburban geology of Richmond, Wayne county, 

 Ind., by Dr. John T. Plummer, vol. xliv., 1843, p. 

 302: — 



" A tusk [of the mastodon or mammoth] was exhumed from 

 the gravel, fifteen feet helow the surface, while excavating the 

 Whitewater Canal, near Brookeville, about thirty miles south of 

 Richmond ; [and] a club-shaped implement, formed apparently 

 of cliff-limestone, was also taken out of the gravel ten feet helow 

 the surface, near the spot where the tusk was found." 



This implement is described as " seventeen inches 

 long, rounded at one end, tapering towards the other 

 extremity." I do not remember to have seen any 

 reference to this in recent works ; but as Dr. Plum- 

 mer seems to have been an intelligent observer, and 

 as he calls attention to the resemblance of this imple- 

 ment to an 'Indian hommony pestle,' and to the 

 remarkable fact that it was found under the above 

 conditions, the note should be borne in mind, and 

 other implements looked for in the gravels of the 

 vicinity named. 



In the same article are noticed an ornament called 

 ivory by Dr. Plummer, but probably shell, as like- 

 mistakes are often made (p. 301), mounds (p. 313), 

 and (on p. 303) "several sticks, and a chip having 

 palpable marks of an edged tool upon it," found 

 nearly thirty feet below the surface in excavating a 

 well in Richmond. F. W. Putnam. 



THE MADISON EDUCA TIONAL CONVEN- 

 TION. 



The meeting of the National educational 

 association at Madison, Wis., which closed its 

 sessions on Friday, July 18, was the largest 

 ever held in this country, and probably the 

 largest of its kind in the world. Ever3 T state 

 and territor} T in the Union was represented, 

 and over six thousand teachers were on the 

 ground. The weather was fine, the town 

 beautiful, and very bountiful in its' hospitality, 

 the excursions numerous, the speakers elo- 

 quent, the exposition, on the whole, more 

 instructive, and in some departments larger, 

 than at Philadelphia in 1876. Everybody was 

 there, was heard, and most who desired it had 

 some office provided for them, and had their 

 names and words spread over the land by the 

 efficient agent of the associated press. Half 

 a dozen meetings were going on at the same 

 time, and manuscript enough to run as many 

 educational journals for the year was evolved ; 

 so that those who went will not need to read 

 for one year. There were committee meetings 



