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THE HOLLY BLUE. Celastrina (Cyaniris) Argiolus. RICHARD S O U T H , at that time the editor of " T h e Entomologist," drew attention in his classic " T h e Butterflies of the British Isles " (Frederick Warne, 1906) to the fluctuation in numbers of this species from year to year, but did not go so far as to say that, in some parts of the country at least, it seemed to disappear altogcther for several years in succession ; that has been the case here.
I lived in Southtown, Great Yarmouth, from April 1 Ith, 1905, to Nov. 1 Ith, 1908, on which latter date I took up residence at Beccles. Düring the Yarmouth residence the obvious direction for handy countryside exploration was Burgh Castle, and its possibilities were fully investigated ; no trace whatever of Argiolus was ever evident, nor was there any elsewhere in or around Yarmouth. It was, therefore, with considerable delight that during my first spring in Beccles, in 1909, I discovered Argiolus to be strongly entrenched in the town itself; there seemed hardly a garden, from the largest to the smallest, which it did not haunt, and I particularly observed it in Fair Close, Station Road, London Road, and in the Churchyard of the Parish Church. It was in Fair Close, however, that I considered the key was provided to the uncertain nature of the appearance of this species in various parts of the country, for the butterflies were out in numbers füll early—towards the end of March. T h e spell of fair weather which brought them out did not, however, continue ; they were caught in a cool period, and I found them sitting about in roads, on footpaths and doorsteps, benumbed, and offering no resistance to being picked up in the fingers. T h e effect of such a disaster for Argiolus is evident; caught in the cold in this way, it is unable to breed, and in July there are hardly any or no butterflies and in the spring following none likewise ; the butterfly suffers another of its periodic eclipses which may last for years until fresh colonisation takes place from some favoured sheltered spot. As far as the neighbourhood of Beccles is concerned, the headquarters of the species in which possibly always a few butterflies succeed in breeding is in Barsham and it is from there that renewed colonisation would seem to take place. Thus, towards the end of July, 1911, the summer brood was evident in incredible numbers over the low meadows towards Shipmeadow, and the females in particular were of over average size—a sign that the species had Struck an ideal patch for breeding ; but it never happened again in this spot.