NATURAL HISTORY SOCIETY OF GLASGOW. 287 



" on the 5th of April, they only stay two clays, and then disappear 

 " as suddenly as they came. Some of them return in the first 

 '•' week of May, and they gather together up to the 20th. They 

 " are about a week on the rock before they lay. I got thirteen 

 " eggs on the 12th May, 1867, which is unusually early. By the 

 " 1st June, they have all laid." 



[In the same year mentioned by Mr. Maclachlan as an unusually 

 early breeding season at Barra, viz., 18G7, Mr. Robert Gray tells 

 us, on the authority of Mr. Alexander Carmichael, that "great 

 numbers died on the ledges in the breeding season." Mr. Gray 

 goes on to say, " Incubation had been delayed till the middle 

 of August, on account of the severity of the weather, which seems 

 to have caused the mortality." After the late and severe winter 

 and spring of 1878-79, I did not find that the incubation of rock- 

 birds was delayed, all my inquiries going to prove that such was 

 not the case, and that they were in no way affected by the late 

 summer. J. A. H.-B.] 



" I have never attempted to count the number of these birds, as 

 " it seems not possible to do so. Captain Elwes stayed with me 

 " ten days or so, and, with the assistance of his servant, he used to 

 " try to come to some sort of calculation, but had to give it up. 

 " Suppose those on the rocks could be nearly counted, it was hard 

 " to say how many were flying in circles, and fishing at sea." 



[ It seems to me that a tolerably fair estimate might be arrived 

 at, if, for a few days, all which could be seen on the rocks were 

 counted every clay for a week at the height of the season, and the 

 average doubled to include the birds away at sea fishing. This 

 plan of course could only be applied at certain stations, as the 

 nature of the ledge-formations of the cliffs of some other localities 

 would, from their irregularity, render such an attempt almost 

 vain. J. A. H-B.] 



RAZORBILL. Alca torda, Lin. 



" There is little to be said regarding the Razorbill, as its habits 

 " are much the same as those of the Guillemot, only that the 

 " Razorbill hatches on the ledges highest up from the water, and 

 " it is a smarter bird on the wing." 



PUFFIN. Fratercula arctica, Lin. 



" Of Puffins there is a goodly number. They frequent the 

 " grassy slopes and burrow into holes. They lay two white eggs, 



