ARCTIC TERN. 
STEUNA MACRUIU. 
The difference between the Arctic and. Common Tern is at once apparent when a specimen of eitlier 
species is examined with care ; it is, however, hy no means easy, unless a close view is obtained, to 
identify the birds while on wing. A few words drawing attention to their distinctive marks may be of 
service. The projecting tail-feathers of the Arctic are decidedly longer than those of the Common Tern ; 
the grey tint on the plumage of the breast of the former is also considerably deeper. The mandibles of the 
adult Arctic Tern are a bright crimson (or perhaps carmine, I hardly know which to term the tint), while 
dull black points terminate the beak of the Common Tern. In addition, the length of the tarsi, which 
measure three eighths of an inch more in the Common than in the Arctic Tern, is an unfailing guide. 
This species, decidedly more addicted to salt than fresh water, arrives off our coasts either in company 
with, or at much the same time as, the Common Tern ; the habits and manner of obtaining a living 
folloAved by the two birds are also exceedingly similar. During my travels in the north I met with 
but few opportunities for inspecting the breeding-haunts of this species — the large colonies on the Fern 
Islands, and a few of the smaller nurseries on the shores of the northern Highland firths, Avhere (not 
unfrequently intermixed with the Common Tern) this species rears its young, being all that have come 
under my notice. While making observations on the birds at the Fern Islands in 1867, I noticed that Arctic 
Terns were breeding in immense numbers, three large and two small colonies being established on various 
parts of this barren and wind-swept group of rocks. While Avatching the birds at one of their largest 
nesting-stations, situated near the centre of the islands, my attention Avas attracted by a flock of over a 
hundred Terns collected on a low rock, that barely topped the AA^aves, some distance further out to sea; 
on pulling quietly up, and examining them through the glasses, I ascertained that they Avere all immature 
Arctic of the previous year, exhibiting darkly marked backs, and breasts suffused Avith a deep orange or 
tawny hue. I ascertained that this conspicuous colouring had led some of the Trinity men belonging to 
the inner lights, Avho professed a knoAvledge of the birds frequenting the islands, to bestoAV on them 
the title of Roseate Terns ; the egg-collector, hoAvever, a nephcAV of the celebrated Grace Darling, Avas 
Avell aware to what species they belonged. These juveniles, I remarked, made no attempt to approach 
the islands on Avhich the adult Arctics Avere breeding, or even to intermix Avith them Avhen on wing ; 
though occasionally absent on fishing-excursions for the best part of the day, they invariably took up 
their quarters, Avhen at rest, on one or the other of a feAV small reefs of rocks near the spot where 
they first came under my obseiwation. 
The old lighthouse that in days gone by warned mariners to avoid the dangers of these rock-bound 
islands stands near the centre of the group ; the light on this antiquated building Avas in former times 
supplied by a large coal fire constantly burning on the summit, and the ashes thrown down from above 
Avere alloAved to accumulate in heaps round the basement, till the surf raised by a heavy gale dashed 
