February io, 1893,] 



SCIENCE. 



n 



one to ten times as great. Many of them have a diameter of 

 less than one fifty-thousandth of an inch and it is probable that 

 there are multitudes of them so small that the highest powers of 

 the microscope do not render them visible. Two thousand of 

 them could swim side by side through the eye of a needle and one 

 could hold in his single hand fifty millions of millions of them. 

 Of the smaller ones it would take 15,625,000,000,000 to fill one 

 cubic inch. 



Now compare these with our mammoth Sequoias. The trunk 

 of one of these trees, to say nothing about its roots and branches, 

 contains at least 300,000,000 cubic inches. It is, therefore, 

 3.135,000,000,000,000,000,000 times as large as a single bac- 

 terium. This number is, of course, inconceivable. It may be 

 read 3 135 millions of millions of millions. The proportion is 

 about the same as that of an ordinary football to the earth itself. 



Again, the duration of the life of many of the bacteria is only 

 an hour. There are 8,760 hours in a year, and in 3,000 years 

 there are 36.380,000 hours. Thus the tree has lived on while 

 more than twenty-six millions of generations of its invisible kin- 

 dred may have lived and died in the stream at its base. From 

 the bacterium to the sequoia, what a span ! Yet the rolling 

 globe on which they live is but a speck in the universe, its 

 diameter too small to be used as a measuring unit for interstellar 

 spaces. As many bacteria could be laid side by side on a linear 

 inch as earths upon the diameter of its orbit around the sun. 

 Compared with the tree, the bacterium is almost infinitessimal; 

 by the side of the earth, the tree is insignificant; in the solar sys- 

 tem, the earth is but a small factor; and if the solar system were 

 annihilated, itwould be millions of years before its loss would be 

 felt on distant stars. Magnitudes are, therefore, relative, and 

 things are great or small according to the standpoint from which 

 we view them. 



Cumberland University. 



DESTRUCTION OF CROWS DURING THE RECENT COLD 

 SPELL. 



BT DR. ROBERT RIDGWAY, SMITHSONIAN INSTITUTION, WASHINGTON, D.C. 



Whether it be the result of disease or exposure, the sufl'ering 

 inflicted on the crows in the vicinity of Washington during the 

 recent severe weather is of great extent, and of such a character 

 as to excite the sympathy of any one familiar with the facts. On 

 the 20th of January my son went rabbit hunting, and on his return 

 told me he bad found many dead crows in the pine woods, and 

 others that were totally blind. The following day I accompanied 

 him to the place where he had found them, and was really aston- 

 ished at the sight presented. Very few crows were seen flying 

 about, but upon entering the thick woods of scrub-pines, which 

 was evidently the roosting-place of large numbers of these birds, 

 they were met with on every hand. Some were lying on the 

 snow, dead and frozen stiff ; many more were perched in the trees, 

 at various heights, in all stages of helplessness. The majority of 

 them could fly, and on our near approach would do so; but in a 

 moment it became apparent that they could not see, for the first 

 thing in their line of flight, as, for example, a branch, would 

 stop them, when they would either flutter to the ground or, 

 changing their course, would continue their flight, to be again 

 checked by a branch, or if they happened to miss any obstruction 

 until clear of the woods (which rarely occurred) they continued, 

 slowly feeling their way, over the open fields, often dropping to 

 the snow-covered ground after flying a few hundred yards. Those 

 which did not fly at our approach were too much weakened from 

 starvation to do so. They were easily caught, and in every in- 

 stance were found to be absolutely blind, except one individual, 

 which had one eye but little affected. In many the eyes were 

 closed and much swollen ; in some one or both eyes had burst and 

 frozen, this having possibly been caused by violent contact with 

 thesharpendsof broken twigs. In all cases in which the eyes were 

 not closed or inflamed the pupil was milky white and the iris 

 bluish. Inability to find food on account of their blindness was 

 evidently the immediate cause of starvation ; for it was found 

 that the dead birds were, as a rule, very much emaciated, while 

 many of the living ones, particularly those which were most 



active, !uid consequently difiicultto capture, were in fairly good 

 condition. It was pitiful to behold their suffering, both from the 

 pangs of hunger as well as from the pain of their wounded eyes. 

 Somotimes the snow beneath the trees was nearly covered by pine 

 needles and small twigs which they had plucked off and tried to 

 eat (they were seen doing this), while several of those which had 

 fallen to the ground were eating snow. 



The extent to which this epidemic, or whatever it may be. has 

 affected the crow population of this locality is not easy to esti- 

 mate. My first impression was that the species was nearly ex- 

 terminated there, since certainly 95 out of every 100 crows seen 

 during the day were perfectly " stone-blind," and 10 per cent of 

 them dead. That this impression was incoriect was, however, 

 proven by the next day's observation, the locality being visited 

 much later in the day, when large numbers were seen coming in 

 from the surrounding country to roost, — all these " able-bodied " 

 crows having been abroad after food at the time of our previous 

 visit. There seemed to be about as many of these as there were 

 of the disabled ones, so the reduction in their numbers will proba- 

 bly not exceed one-half, and may not be so great. 



A third visit, several days later, showed no increase among the 

 afflicted birds. There were, however, as might have been ex- 

 pected, a much larger number of dead ones, while those still 

 living were found more scattered, being encountered nearly every- 

 where in the open fields, where they had fallen, exhausted, during 

 their flight from the woods. 



So far as I was able to discover, after very careful examination 

 of all specimens within reach, during both visits, only the com- 

 mon .species, Corvus americanus, was affected by the malady. 

 At any rate, neither my companions nor myself could discover a 

 single fish crow (C ossifragus), though the latter was well repre- 

 sented among those which were flying about. 



I am at a loss to account for this scourge. Several causes have 

 been suggested, the most plausible of which, it seems to me, is 

 that in returning to their roosting-place one excessively cold 

 evening they were compelled to face a freezing wind, perhaps 

 bearing minute ice-particles, which actually froze their eyes. It 

 may be, however, that a better explanation can be given. 



REMARKS ON AMERICAN LICHENOLOGY. — III. 



BY W. W. CALKINS. CHICAGO, ILL. 



The explorers for lichens in a locality so favorable as Florida 

 will not fail to notice the abundance of brilliantly colored fungi, 

 and. if interested, will be tempted to collect them. On some of 

 these will perhaps occur parasitic lichens of rarity, as Colno- 

 goniuin and Opegrapha. But beneath a bed of Agaraci, on the 

 sandy soil of an old plantation, a close search will show another 

 interesting lichen, known as Heppia despreaiixii Tuck. Its char- 

 acter was long disputed, owing to a close resemblance to an allied 

 genus of lichens, Solorina. The small cup shaped apothecia, 

 growing single or in clusters, immersed in a green thallus, have- 

 deceived good lichenists. We owe to Dr. Tuckerman the eluci- 

 dation of this eiegent species. Only two were described by him 

 in the ''Synopsis." Last winter I had the good fortune to find 

 another in the mountains of Tennessee, which, having been sent 

 in vain around our own country, a puzzle to all, was promptly 

 determined by Dr. Nylander of Paris to be the Heppia virescens, 

 Ach. variety rugosa Nyl. I may remark that it is astonishing 

 how soon afterwards we all saw the point. 



In the old field as well, with a mixed second growth of Pinus 

 taeda, Ilex opaca. Ilex Cassine, Myrica cerifera, Olea americana, 

 etc., will be found on their foliage numerous small fungi, such as 

 Sphaeria and Cercospora, many of which have been illustrated 

 by Professor Ellis in his "Exsiccati" from my collections of 

 fungi. 



In close contact, lichens and fresh- water algae and Hepaticce also 

 hold equal sway. But, towering over all, the stately Magnolia and 

 the Gordonia (red or bull bay), with their glossy evergreen foliage, 

 afford us the tropical lichen, Strigula complanata Fee., and, rarer 

 still, Heterothecium augustini Tuck., though, indeed, the Sahal 

 serrulata, common everywhere, abounds in elegant specimens in 



