BIRDS have found the egg of the cuckoo in a nest of this species. 11. Redstart. Ruticilla phxnicurus (Linn.). This is a common summer migrant which is found in considerable numbers wherever suitable nesting-places can be obtained. In 1886 one was seen at St. Albans on March 28th, but its usual date of arrival is about the second week in April. The nesting sites chosen by this bird are very varied : during the present year (1900) I found a nest in a hole which had apparently been dug out by a sand-martin (Cotile riparid) in a claypit at a brick kiln near Berkhamsted. 12. Black Redstart. Ruticilla titys (Scopoli). We are indebted to a Mr. A. Sainsbury Verey, of Heronsgate near Rickmansworth, for the addition of this species to the county list. In a letter to the Watford Observer of April ist, 1893, he stated that, while watch- ing for wheatears in his field, the note of a redstart attracted his attention, and on looking at the bird he was immediately struck by its dark back as it sat perched on a wire fence not far away. The bird permitted a close ap- proach, and turning round showed the dark colour of its throat and body, thus confirming his first impression that it was an example of a black redstart. In a further letter to Mr. Henry Lewis, Mr. Verey said that the bird was first observed on March 28th, and that it stayed for two days, and being very tame, gave him ample opportunities of studying it and determining its species. 13. Redbreast. Erithacus rubecula (Linn). This bird, as in other counties, is an extremely common resident, and many are the curious nesting-places that have been chosen by it in Hertfordshire. One or two albino or partial albino varieties have also been obtained, while on two occasions at least pure white eggs of the robin have been found in the place of those of a normal colour. 14. Nightingale. Daulias luscinia (Linn.). This, the finest of our native songsters, is to be found pretty generally distributed throughout the county, although perhaps towards the north it is hardly as plentiful as elsewhere. The earliest record I have of its arrival is April 7th, on which date it was seen at Harpenden in 1884. 15. Whitethroat. Silvia cinerea (Bechstein). The common whitethroat is very plentiful throughout the county, usually arriving about April 20th. 1 6. Lesser Whitethroat. Silvia curruca (Linn.). This is a bird which in Hertfordshire seems to vary greatly in numbers in different years, sometimes being very plentiful, but at others quite uncommon. It generally arrives about the same time as the last-mentioned species. 17. Blackcap. Silvia atricapilla (Linn.) This is a common summer visitor to Hert- fordshire, appearing about the middle of April. In 1896, however, Mr. H. R. Rivers observed it at Sawbridgeworth on March 24th. In May, 1900, I came across two nests of this species, which varied considerably from the usual nest of a blackcap ; instead of being made of grass on the outside, they were com- posed chiefly of sheep's wool with a little grass mixed with it. 1 8. Garden- Warbler. Silvia hortensis (Bech- stein). The garden-warbler seems distributed throughout the county, though not in large numbers. It prefers the neighbourhood of woods, and usually arrives towards the end of April. 19. Dartford Warbler. Silvia undata (Bod- daert). Hertfordshire should be an ideal county for this bird on account of its many gorse-covered commons. It was not however until 1897 that it was actually identified with us. On May ist of that year Mr. Charles Worte with a friend, both of whom were well ac- quainted with the species, recognized a pair of these birds on a small common, known as Commonwood Common, near Chipperfield, and watched them for some time. It is prob- able that the Dartford warbler may in the future be recognized on other commons in the county, as Mr. Harting recorded its occur- rence in Middlesex on Stanmore Common, which is only just outside Hertfordshire, as long ago as 1866. Mr. Worte considered that the birds seen by him were nesting. 20. Goldcrest. Regulus cristatus, K. L. Koch. This pretty little bird is distributed all over the county, but being partial to fir-trees is not so common in Hertfordshire as in counties where such trees are more abundant. 21. Firecrest. Regulus ignicapillus (Brehm). An example of this species was obtained at Tring on January ist, 1887. There is also a statement in the Transactions that the firecrest had occurred at Bennington near Stevenage on the authority of Mr. Chapman of that place, who had often seen them there. 197
