Aug. 11, 1870] 
opinion respecting the corona could be made public. At present 
all that is generally known is, that he regards the corona as ** an 
effect due to the passage of sunlight through our own atmosphere 
near the moon’s place.” Those are the words he used (see 
Narurr, vol. i., p. 14). Limagined that I had understood them. 
Tt seems I had not. Will he explain them, and perhaps indicate 
how the sunlight gets there? I only need to learn how one ray 
of sunlight can reach the atmosphere near the moon’s place, 
during central totality in any considerable eclipse, and why the 
atmosphere actually a¢ the moon's place (that is, all that cone 
of air which lies between the eye and the moon) is leit free of 
this sunlight. This being satisfactorily explained, I should waive 
all other objections and accept the atmospheric glare theory 
without further question. RICHARD A. PROCTOR 
[Mr. Proctor should have quoted the context, in which Mr. 
Lockyer carefully refers to Dr. Frankland’s and his own con- 
clusion (or theory) ‘‘against any such extensive atmosphere as the 
corona had been imagined to indicate.” He then states that 
the “conviction” that the corona is probably‘ an atmospheric 
effect, “is growing stronger and stronger,” if the negative 
evidence of the new methed of observation were alone taken 
juto account; but this is not to elaborate a theory.—ED. ] 
The Horse-Chestnut 
REFERRING to NATURE, No. 37, your correspondent, Eugene 
A. Connell, has fallen into a mare’s nest in the matter of the 
horse-chestnut. 5 
Country people are well aware of the impression of the horse’s 
foot he has discovered, but the coincidence is quite accidental, 
and has nothing to do with the name. 
“*Horse” isa very common prefix, denoting largeness or coarse- 
ness, in the same way that the prefix ‘‘dog ” indicates inferiority 
and contempt. Thus we have horse-chestnut, horse-bean, horse- 
radish, horse-mint, horse-parsley, horse-leech, dog-rose, dog- 
violet, dog-berry (the berry of So/anum nigrum), &c. 
These prefixes are common to nearly all languages ; we have 
fmmd-kpnuvos, a horse-laugh, ‘‘fievre de cheval,” a violent fever, 
and a host of like terms. 
Bath, July 27 CHARLES EKIN 
The “English Cyclopedia” 
IF the Editor of the “ English Cyclopzedia,” in his letter con- 
tained in your issue of July 7, had restricted himself to defending 
his own handiwork, and had abstained from denying the cor- 
rectness of my statements, I should not have ventured to ask 
for space in your columns to reply to him. 
In opposition to my statement that I looked in vain for 
"< 4Arvicole, Crocidura, Crossopi, Hypudei, Sorices, shrews, and 
voles,” the Editor asserts that ‘‘all the species mentioned 
in the Close Time Report are described or noticed in the Cyclo- 
pedia.” This may be and probably is quite true. I merely 
asserted that they were not to be found under their respective 
names. Ihave stated that I found Aypudeus and the voles 
under the heading AZzride. In return for my information he 
now tells me that if I wished to become acquainted with 
Crocidura and Crossopus I ought to have turned to the article 
Sorecidz. But how is an unlearned reader like myself to know 
where to turn? The Editor only confirms the accuracy of my 
statement as to the great want of cross references. If the In- 
dex and the Supplement had contained such references as 
Hypudeus [Muridz, E.C.], Crossopus [Sorecide, E.C.], &c., I 
should probably never have given public utterance to my 
troubles. In reply to my assertion that I looked in vain for an 
article on Rhizocrinus, 1 am told, much to my astonishment, 
that the proper place to find it is under London Clay. In my 
ignorance I had sought for it under its own name, Afzocrinites, 
and Zncrinites. According to this mysterious system of arrange- 
ment, if I had complained that there was no article on Sfarrows, 
I should probably have been told that I ought to have looked 
for a notice of them under the heading London. 
In my letter I gave a list of twenty-three important subjects 
on which there were no articles. In defence of these real or 
apparent omissions the Editor, after making the strange asser- 
tion that two of these, Acc/imatisation and Deep Sea Dredging, 
belong rather to the ‘Arts and Sciences” than to the 
““ Natural History” division, goes on to say that most of the 
subjects stated by me to have been omitted ‘‘do occur.” He 
NATURE 
297 
must be well aware that I never asserted that they ‘‘do not 
occur.” I simply said that there were no special articles on 
them. He might have had the candour to notice that I un- 
earthed from their hidden recesses the subjects to which he 
expressly refers in his letter, viz., Zophyton, Eoz0on, Hyalo- 
nema, and Frotoplasm. 
As I must not trespass further on your space, I will conclude 
by observing that I fully concur with the Editor in the opinion 
that ‘‘ what a Cyclopzdia ought or ought not to contain is an 
Open question ;” but when an Editor has the mora! courage to 
assert, in illustration of the mode in which he discharged his 
functions, that ‘* AZe/oe was inserted and Sphevide rejected, be- 
cause there was not room for both,” and gives no less than 
twelve columns to the former instead of dividing the space be- 
tween the two; and when he tells us that Zondonw Clay is the 
proper place to seek for information regarding Riizecrinus, the 
readers cf NATURE may draw their own inferences as to what 
a Cyclopedia, under his superintendence, is likely to be. 
1 must add that I have not the slightest idea who the Editor 
of the Supplement is, and that until his letter appeared, I did 
not believe in his existence. 
South Devon, July NEMO 
Entomological Inquiries, etc. 
I was much interested, two nights ago, at finding on the wall of 
my drawing-room a flattish, dark-grey winged insect, six or seven 
tenths of an inch in length, which, on being placed in the hand, 
exhibited two small but brilliant sparks of light towards the 
extremity of the tail. In the imperfect light in which it was 
examined, the wings seemed to have elytra and the body to be 
somewhat like a small caterpillar, with a tapering tail. In size 
and general aspect it resembled the Italian fire-fly, with which I 
made acquaintance last summer on the Lake of Como, without, 
however, a sufficient examination to justify more than the most 
superficial comparison. My knowledge of entomology is so 
defective, that I feel unable to form an opinion whether it might 
be that insect or the male of the common glow-worm (which, 
however, is not common in my neighbourhood). If so meagre a 
description may enable any of your readers to give me satis- 
factory information as to this point, I shall feel much obliged to 
them. 
There is adéquate evidence that some kind of fire-fly has been 
seen during hot seasons in England. Kirby and Spence give a 
reference, which I have no opportunity of verifying, to Phil: 
Trans. 1684, as to their appearance in Hertfordshire, and their 
having been considered the genuine ZLamfyris ttalica. The 
following unpublished account may be interesting as having come 
to me from a perfectly reliable source : ‘‘ In 1822—the year is 
pretty certain—during the month of June or July, the weather 
being very hot, on at least two evenings a number of fire-flies 
were seen at a village near the Thames, between Reading and 
Henley ; they were flying about the fields and the lawn before a 
gentleman’s house, and some of them came into the house ; three 
or four or more might be seen at a time, like little flying lamps. 
The insect was brown [reference is then made to a sketch from 
memory thirty-two years afterwards, from which it must have 
greatly resembled my specimen], and seems to have had opaque 
elytra and network wings ; the light was in the tail, like that of 
a glowworm, as bright, but probably not as large. A very 
intelligent gentleman who was upon the spot, an acquaintance of 
Dr. Wollaston’s, who had been in America and the West Indies, 
was greatly astonished; he caught some of them, and considered 
them identical with the West Indian firefly. He said he had 
heard of their being in England, but never seen them.” 
A lady, whose experience must be referred to a later date than 
the foregoing account, has informed me that she once observed 
them for a single day in Wiltshire. 
The newspapers of 1868 or 1869—I am not certain which— 
spoke of them as abundant in some places ; particularly, I think, 
at Caversham in Kent, where they were even considered 
*‘nuisances !” if I recollect right. Some of the readers of 
NATURE may perhaps be able to furnish information as to this 
alleged fact. 
There is something very remarkable in the occasional appear- 
ance of these beautiful insects in our climate. They can hardly 
be thought to reach us by direct migration. Can it be supposed 
—as it has been ingeniously suggested to me—that their ova are 
frequently being imported from warmer countries, but are only 
fully developed in the temperature of our hottest summers ? 
