BERRY, Wallington, late 19th century
The Plough Public house has been in Wallington for a long time - a quick check shows it was there in 1850 (Post Office Directory), it is marked on the OS Map of 1883 (old maps) and in early 20th century sources such as the 1903 Little Guide - and for all I know may still be there.
The 1881 census shows two "alcoholic beverage" establishments - The Plough with 48 year old James Spriggs described as an innkeeper, and an unnamed beerhouse with 52 year old John Scoote described as a beerhouse keeper. I don't have access to the 1891 census - but I suspect that if you look again you will find that the Plough is also listed. If you want to know if the 1881 beerhouse is the same place as The Harrow Inn the 1891 census you may be able to find out by comparing the neighbouring properties in the two censuses.
It is worth commenting that many beerhouses in rural areas were small establishments where the landlord carried out another occupation during the day - but sold beer in the evening as well. Many records, such as trade directories and census returns do not bother to record a name, while Inns - which provided a wider range of services - are almost always named.
You failed to give sufficient information to uniquely identify Thomas and Emma Berry but in the 1881 census a 39 year old Thomas Berry (policeman, born Aston, Herts) and his 39 year old wife Emma (dressmaker, born Stevenage, Herts) were living at Westside Cottage, Offley, Herts, with a large family, including a 15 year old son, Thomas (agricultural labourer, born Great Hadham, Herts). Obviously if these match with the information you have from the 1891 census you will want to check the 1881 census for yourself.
If you can add to the information given above tell me.