(230) NOTES ON OUTER HEBRIDEAN . BY C. M. N. WHITE, B.A., M.B.O.U. SINCE Colonel Meinertzhagen pointed out (Ibis, 1934, pp. 52-61) that the present a particularly interest­ ing feature of geographical variation in certain species, several short notes have amplified details. My own studies of the subject have caused me to visit , Harris and Knapdale, Argyllshire. The suggestion that high atmospheric humidity was the factor to which these heavily pigmented races were due, must now be viewed in the light of certain fresh data. For one important feature which has emerged is the discovery that some Hebridean races occur on the western mainland. This has apparently lead to the suspicion that other birds found on the western mainland but not reaching the Outer Hebrides may form similar new races distinct from those of elsewhere in Great Britain. In Knapdale I paid attention to common Passeres which do not occur in the Outer Hebrides, and do not consider that any of them form distinct races. The idea to the contrary, it may be pointed out, has been partly fostered by the examination of certain soot-stained birds which give an apparent but quite misleading impression of dark pigmentation. Consequently any material quoted from industrial areas of south-west requires an assurance that this source of error has been eliminated in making a comparison. It is interesting to note that no general rule can be enun­ ciated for the distribution of Outer Hebridean subspecies. The Rock-Pipit and Wren are known only from the Outer Hebrides ; the Stonechat and Hedge-Sparrow are found on the western mainland; the Song- is represented by an intermediate in west Scotland; the also occurs in the ; the Red Grouse and perhaps the Dipper are of the Irish form. It is not out of place to add that our knowledge of the range of these subspecies is in many cases far from complete, and as they are mostly common species it should not be difficult to fill in gaps in the Inner Hebrides and west Scotland, whilst Ireland also merits further attention in this respect. In addition to Outer Hebridean races, I have included a few records of interest of other species. STARLING (Stumus v.' zetiandicus).—Common in N. TJist, Harris and Scalpay ; birds which. I observed spent a great deal of time feeding on the shore among seaweed. In the field the dark colour VOL. xxxi] OUTER HEBRIDEAN BIRDS. 231 of the juvenile was particularly striking. Juveniles from Scalpay examined are moulting into first winter plumage, but the remains of the juvenile plumage are still darker than in similar typical vulgaris. Adults seem to differ only in size—three males have wings 133, 136, 138 mm. against 126-134 m twelve males from England. HOUSE-SPARROW (Passer d. domesticus).—This is now very common about human habitations in N. Uist, Harris and Scalpay. BRITISH CHAFFINCH (Fringilla c. gengleri).—Birds from Knapdale are not different from those from elsewhere in Great Britain. MEADOW-PIPIT (Anthus pratensis).—A juvenile fromN. Uist is excep­ tionally heavily streaked with black both above and on the breast, and is darker brown above than juveniles from England. However, adults from S. Uist to Harris show no peculiar characters ; further juveniles would be of interest. HEBRIDEAN ROCK-PIPIT (Anthus s. meinertzhageni).—This is perhaps the best marked Hebridean race, being a blackish-grey instead of olive-brown bird above, with very heavy breast streaks. It is so far only known from S. Uist, Benbecula, N. Uist and Scalpay. Birds examined from Skye and Muck are not this form. In my experience Rock-Pipits in the Hebrides are as much birds of the moorlands near the sea as of the actual shore, and are commonly found in company with Meadow-Pipits. ROCK-PIPIT (Anthus s. petrosus).—I collected one bird on Scalpay which is not the Hebridean form ; it appears to me inseparable from British examples and I must therefore refer it to that form with the caution that it may prove to belong to the Faroe form, which does not seem distinguishable in autumn plumage. It was with Greenland Wheatears, and this perhaps suggests the latter view. BRITISH SONG-THRUSH (Turdus e. ericetorum).—This form may be a winter visitor to the Outer Hebrides, as a bird from N. Uist (January 23rd, 1936) shows, unless it came from Stornoway, where typical ericetorum is known to breed. Birds from south-west Scotland are much nearer to this form than to T. e. hebridensis, which they slightly approach in a rather darker upper surface and particularly greyer rump. The difference does not seem quite sufficiently constant to justify a distinct race being named. HEBRIDEAN SONG-THRUSH (Turdus e. hebridensis).—In June and July in N. Uist the Song-Thrush appeared to be scarce, but I am inclined to ascribe this rather to breeding than to actual fact, as birds were very difficult to find in the long heather. In Harris it was more numerous in September, but very wild. A bird from Scalpay was on the shore and had eaten several small crabs. BLACKBIRD (X. m. merula).—I only once saw a Blackbird in N. Uist, June 29th, 1935, but they were several times observed in gardens in Harris in September. The only female I saw looked remarkably dark. ROBIN (Erithacus r. melophilus).—Robins were common in croft gardens about Tarbert and one was seen in Scalpay, September, 1937. They included juveniles moulting into adult plumage. Argyllshire Robins are typical melophilus. GREENLAND WHEATEAR (CEnanthe ce. leucorrhoa).—A female was obtained in Harris on September 16th (wing 106 mm.) and others were seen in Harris and Scalpay. HEBRIDEAN STONECHAT (Saxicola t. theresae).—Birds from N. Uist and Scalpay are of this race ; juveniles do not appear to differ in colour from those of hibernans. Published records suggest that it is rather uncommon in the Outer Hebrides, but in N. Uist it was tolerably 232 BRITISH BIRDS. [VOL. XXXI. common and not uncommon in Harris. I have examined in the Royal Scottish Museum a small series from the Butt of Lewis, also of this form. HEBRIDEAN HEDGE-SPARROW (Prunella m. hebridium).—A bird from Harris is of this race. It appears distinctly scarce in the Outer Hebrides though quite common in Knapdale, where the Hebridean form is found. Hedge-Sparrows from Lancashire approach this race in the colour of the head. In my experience the dark colour of the Hebridean race is quite noticeable in the field. HEBRIDEAN WREN (Troglodytes t, hebridensis).—Common in N. Uist and Harris ; not noted in Scalpay. A single bird from Knapdale is to me identical with the typical form. BUZZARD (Buteo buteo).—Two pairs bred in N. Uist in 1935. In April, 1936, I saw four Buzzards near Sweyn, Knapdale, on several occasions. KESTREL (Falco t. tinnunculus).—In April, 1936, when voles were numerous in Knapdale Kestrels were correspondingly numerous ; in July of the same year members of the Oxford Ornithological Society were surprised at their scarcity, which was also true of April, 1937. Their presence in numbers together with the Buzzards noted above was evidently due to the exceptional number of voles. In June, 1935, in N. Uist Kestrels were also exceptionally numerous, but I was unable to get any data about voles ; however, in September, 1937, I saw only one Kestrel in Harris so that the same factor may have determined their numbers in these localities also. SOOTY SHEARWATER (Puffinus griseus)—-GREAT SHEARWATER (P. gravis),—I saw one Sooty and two Great Shearwaters between Canna and S. Uist on September 13th, 1937, flying north-east. The cap contrasting with the back in P. gravis is most striking to distinguish it from P. kuhlii with which I am very familiar, and this experience of P. gravis makes it possible to confirm the correctness of my identi­ fication of P. kuhlii off the Sussex coast in September, 1936.