Frederick Merrifield was an English

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 entomologist.

Merrifield was a London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

 attorney

Lawyer

A lawyer, according to Black's Law Dictionary, is "a person learned in the law; as an attorney, counsel or solicitor; a person who is practicing law." Law is the system of rules of conduct established by the sovereign government of a society to correct wrongs, maintain the stability of political...

. An expert on Lepidoptera

Lepidoptera

Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

, he was especially interested in the effect of temperature on the colour and patterning of butterflies, rearing larvae and pupae in controlled temperature incubators and recording the effect on the colouration of adults. Examples of his very many scientific papers on this subject are (1890). Systematic temperature experiments on some Lepidoptera in all their stages. Trans. Entomol. Soc. London, 131-59 and (1891). Conspicuous effects on the markings and colouring of Lepidoptera caused by exposure of the pupae to different temperature conditions. Trans. Entomol. Soc. London, 155-67.

He was President of the Royal Entomological Society (1905-1906).