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its mouth after working it up in a pellet. The hee had either forgotten to lay its egg, or the egg had died; it does not matter to us much which; but it has enabled me to state that this bee does collect pollen, like almost and perhaps all other constructive bees."—Page 70.

I may explain here that Colletes and Prosopis (Hylaeus) are the two genera of bees that have obtuse instead of acute tongues, and are "the only two that plaster their nests with a peculiar goldbeater-skin-like substance, for which their tongues are admirably adapted."

A word on Mr. Barrett's paper. It may seem an easy thing to take Doubleday's 'Synonymic List' into the woods and lanes, to tick off with a pencil every butterfly or moth observed, to repeat the same process week after week, and even month after month, for four years, and finally, when nothing new turns up, to make a catalogue of all the species so ticked off and send it to the printer; but really a great deal of labour, patience, perseverance and knowledge are involved in the task, and Mr. Barrett has brought all these qualifications to his assistance.

There are comparatively few Lepidoptera peculiar to Norfolk; hence although this Catalogue contains a most ample list of species and localities, it has no absorbing general interest, and serves rather to illustrate the industry of the writer, which is most unquestionable, than to extend our knowledge of the science: this observation is by no means peculiarly applicable to Barrett's list; it applies with equal and indeed with greater force to other similar lists which have appeared in all our Natural-History periodicals.

I observe that many previous errors and misstatements are repeated, solely for the purpose of contradicting and condemning them. Thus Chortobius Davus, Thecla Spini, Polyommatus Dispar, Arcturus Sparshallii and Eutricha Pini are introduced, although Mr. Barrett is perfectly aware, and states explicitly, they have no place in the Norfolk Fauna. There is no misrepresentation, but rather supererogation in this unnecessary detail.

There are apparently six species confined exclusively to Norfolk, so far as the British Islands are concerned; these are Lithosia muscerda, Nonagria brevilinea, Crambus paludellus, and Sericoris Doubledayana, confined to the fens; Crambus fascelinellus, inhabiting the sandy denes at Yarmouth; and Nothris verbascella, attached to the very local mullein (Verbascum floccosum), which grows so abundautly around Norwich.

The advantages likely to result from the constant repetition of such names as llapae, Napi, Rhamni, Urticae, lo, Atalanta, MegEera, Janira, Phlaeas, Alexis, &c, in this and all similar lists, may very reasonably be called in question; yet it is by no means desirable to omit them, for such omission would itself seem a matter of interest, seeing that their absence from Norfolk would be far more remarkable than their presence.

Edward Newman.

Migrations of Spring Immigrants. By R. M. Barrington.

I Send you the dates on which a few well-known summer migrants have arrived in this neighbourhood for some years past. I regret that the record is not as perfect as I could wish; but as Irish observations are not plentiful these may prove acceptable.

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Looking at the dates above given, we see that the cuckoo and corn crake make their appearance with tolerable regularity. The swallow is apparently less regular. I refrain from making any remarks on the other two birds until I have accumulated a few more observations.

On the migration of birds in general I venture a few words, which, if not new, have at least the merit of being origiual. Ornithologists who keep records of the departure and arrival of migratory birds must in the course of time form opinions based on the statistics which they have accumulated. All I would wish to do here is to point out a few circumstances which should, 1 think, qualify some of the results derived from such statistics. We say that such and such a bird arrives in this country in April, but the

* The earliest date, so far as I can discover, ever recorded in Ireland.—It. M. B.

date on which it appears is very uncertain; another bird is stated to appear with regularity. Again, we say, one bird comes eight or ten days after another, and so on. Let us first consider the regularity with which migrants make their first appearance, and then the average date of the first appearance.

Some migrauts are first detected by the ear, as the cuckoo, corn crake, chiffchaff, whitethroat, &c.; others by the eye, as the Hirundinidae, the flycatchers, &c. Those detected by the ear may be subdivided into those which make remarkable and loud sounds, as the cuckoo and corn crake, and those whose note is less striking and less intense, as the willow wren, chifTchaff, whitethroat, &c. Few will controvert the statement that some migrants are large and others are small. Birds, such as the cuckoo and corn crake, which announce their arrival over a comparatively wide area, and whose first appearance is readily detected, should afford tolerably accurate results. Conclusions based on the appearances of such species as the willow wren and chiffchaff will be less correct; and those birds which are generally detected by the eye will furnish results which contain a still larger amount of error. Any circumstance, in fact, whether it be due to the size, the note, or the habits of the species, or to the habits of the observer himself, which tends to diminish the probability of detection and facilitate concealment, lessens the value of the statistics we have been speaking of, and frequently, in my opinion, leads us to imagine that a bird is uncertain in its appearance when in reality it is not. The observer himself is an important element: if he is not situated in a favourable position; if he is here one week and there the next; if he is irregular in his habits; and lastly, if he is not a careful ornithologist, his observations are worse than useless.*

As to the average first appearances, a single example will show how easily we may be misled. Let us compare the spotted flycatcher and the cuckoo: suppose a single specimen of each species to arrive, if it were possible, on the same day during twenty years in a wooded demesne one mile square, the chances I should say are ten to one, perhaps more,—even in the case of a good observer,—but that he detects the cuckoo some days before the flycatcher; and perhaps, if we judge from his twenty years'

* I am increasingly of opinion that these records of arrivals which occupy so large a space in our journals aro without any scientific value, and are of interest only to the respective writers.—Edward Newman.

SECOND SERIES—VOL. IX. 2 Q

observations, the latter bird will apparently have arrived a week later than the former. If the observer is incompetent or lazy, and sits in his parlour until the flycatcher appears opposite the window, I need hardly say the error is vastly increased. This case is only an illustration of many similar ones.

At present I have little more to say on this subject. Perhaps some will consider that I have already made a mountain out of a molehill; it may be so, but such was not my intention. I merely wished to direct attention to a few points which should, I think, qualify some of the conclusions we draw from statistics, showing the arrival of migratory birds: how we should take into account the circumstances which iufluence the probability of detection— namely, the size, note, and habits of the bird; how we should consider also the habits and competency of the observer, and how careful we should be to select those which are trustworthy and accurate. If these things be allowed for, I am of opinion that birds will be found to migrate with greater regularity than is sometimes supposed, and that the average first appearance of some migrants should be placed at an earlier date than the conclusions founded on observations would lead us to believe was the correct one.

Richard M. Barrington.

Fassaroe, Bray, Co. Wicklow,
May 3, 1874.

Ornithological Notes from Devonshire, Cornwall, Sfc.
By John Gatcombe, Esq.

(Continued from S. S. 3945).

March, 1874.

2nd. Observed a large flock of herring gulls congregated at their usual breeding-place near the Rhame Head on the Cornish coast, a few miles from Plymouth; they were crying loudly and uttering their peculiar laughing or alarm-notes, as in the nesting season. Remarked also an immature black redstart at the Devil's Point, Stonehouse.

4th. Guillemots and razorbills are now to be obtained in every stage of plumage, from the immature of the year to the perfect breeding-dress.

8th. There were several dabchicks on the Laira to-day. The way in which these birds manage to evade pursuit when hard pressed is truly wonderful. I have known them, after having tried their utmost for a long time to escape by diving in the open water, to suddenly disappear in a manner the most unaccountable, especially to those unacquainted with their habits; but on repairing to the shore and disturbing the weeds, or anything that may afford the least concealment, with your paddle, you will observe something suddenly dart out from under, just like a flatfish, leaving a line of muddy water in its wake, should it be very shallow, and on keeping your eyes in the direction it took,, up will pop the dabchick, perhaps just within gunshot, on the surface; but down it goes again in an instant, before you can take even a " snap-shot." On some occasions I have seen them fly suddenly off from their place of concealment, and on alighting instantly dive. They make use of their wings as well as their legs to propel themselves when under water; and when among the weeds they must continue to sink their bodies, so that only the top of their heads, or perhaps bills alone, would be above, and which of course it would be almost impossible for one to discern among the surrounding objects. I have sometimes observed dabchicks in bays on the sea-coast, especially near the entrance of an estuary or large river.

9th. The weather has suddenly become very cold, with heavy snow storms, but I have observed none of the thrush and lark tribe flying from east to west, as they invariably do during snow storms in the earlier part of the winter.

12th. Took a walk in the country a few miles from Plymouth, and found that all the redwings and almost all the thrushes had disappeared during the snow.

13th. Saw the first wheatear for the season, and some herring gulls in perfect breeding-dress.

14th. There was a beautiful male garganey brought to the birdstuffer's, killed in a pond near Plymouth, and I saw another in the market: I understand that several others (all males) have been seen and obtained in Cornwall and the north of Devon within the last few days. Lesser blackbackcd gulls have now become very plentiful, just as they were last season; before the breeding season they appear to arrive on our coasts in great numbers.

20th. Curlews have been moving about a great deal by night lately.

23rd. There were some golden plovers in the market with nearly perfect black breasts. Saw a very pretty variety of the hedge

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