[...] following the-widespread immigration of 1859 a larva was found at Hartlepool by Mr. Appleton, with another at South Shields on 24 September 1861 (C. Eales) that yielded an imago on 18 July 1862. In 1870, another year of widespread immigration [...] Mr. Ritchie found one in a Hartlepool shipyard, while Mr. Hamilton took a larva from an engine shed (thought to have been brought with sand used on the engines) that yielded a perfect imago on 30 April following. Renewed immigration [occured] over the British Isles in 1888 [...] Robson also received two imagines, and later in the autumn J. Gardner found two larvae on the sandhills north of Hartlepool, which, however, he failed to rear. This brief account completes the records now available to us for Robson's era. Thereafter there was a long gap until 1935 when A. Bolton brought J. W. H. Harrison a larva collected from willowherb near Birtley on 18 August: seven more were later obtained, from which four females and two males were later reared, emerging 6-14 July 1936 (Vasc. 21, 153 and 22, 111). In the same period eight imagines were bred from c. 20 eggs taken near the L.N.E.H. engine works at Darlington (W. Standing): on 24 June 1936 a fine specimen was taken and released at West HartIepool by J. W. Goldson (Vasc. 22, 97). The suspicion of breeding and winter survival raised by the latter record received support during the next marked irruption that began in 1973 when imagines were noted from [...] Stanley and Peterlee [...] while larvae were found at [...] Shildon, Boldon, Durham City and Bishop Auckland. [...]