Surname known only from that of her presumed sister (ie sister-in-law to her husband), Katherine Maud Bonnet aged 16 and also born at Maddington, Wilts, in the house with her at the time of the 1881 census.

But her marriage record on FreeBMD says she was ‘Ada Ginevra Bennett’; the surname I find more believable, not sure about the second name.  But ‘Ginevra’ is very clear on the marriage index.  So is ‘Ginevra’ on the birth index.
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No death record on FreeBMD before 1935, even though he reported himself to be a widower in 1911.  I searched for all these between 1901 and 1911 and born in 1853:
ada sket*
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Found in the 1861 cesnsus with her parents and siblings; her father was, on the enumerator’s sheet as “Vicar of Heronton(?) and Perpetual Curate of Maddington”:


First name(s) Last name Relationship Marital status  Gender  Age  Birth year  Occupation  Birth place

Frederick Bennett Head Married Male 39 1822 ... Wimbledon, Surrey, England
Ellen Bennett Wife Married Female 38 1823 ... Wife  Wiltshire
Maria Louisa Bennett Daughter - Female 14 1847 Scholar  Maddington, Wiltshire
Edith Ellen Bennett Daughter - Female 13 1848 Scholar  Maddington, Wiltshire
Margaret Emily Bennett Daughter - Female 11 1850  Scholar  Longbridge Deverill, Wiltshire
Ada Bennett Daughter - Female 7 1854 Scholar Maddington, Wiltshire
Mary ... Bennett Daughter - Female 5 1856 Scholar  Maddington, Wiltshire
Gertrude Elizabeth Bennett Daughter - Female 3  1858  -  Maddington, Wiltshire
Ethel ... Bennett Daughter - Female 0 1861 -  Maddington, Wiltshire
Elizabeth A James Servant Unmarried Female 22  1839  Cook  Devizes, Wiltshire
Jane Pierce Servant Unmarried Female 22 1839 ...  Wiltshire
Ann Pierce Servant Unmarried Female 19 1842 Housemaid  Wiltshire
Sarah Whatley Servant Unmarried Female 14 1847  ...  Maddington, Wiltshire
Lavinia M Bronerhead Servant Unmarried Female  28  1833  Governess  Lincoln, Lincolnshire
Fanny Sharps Visitor Widow Female 56 1805 ...Widow  Sutton Veny, Wiltshire

Address & Ref:

House name Parsonage
Street Maddington Street
Parish Maddington
County Wiltshire
Country England
Registration district Amesbury
Enumeration district 4
Archive reference RG09
Piece number 1310
Folio 51
Page number 8
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She died between the 1901 and 1911 censuses. This might be her death, though her birth year is a tad late:

First name(s) ADA G
Last name BENNETT
Gender Female
Birth year 1856
Age 54
Death quarter 3
Death year 1910
District Pancras
County London
Volume 1B
Page 52
Country England
Record set England & Wales Deaths 1837-2007
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Their marriage:

Surname First name(s) District Vol Page
Marriages Jun 1876
BENNETT   Ada Ginevra Amesbury 5a 332   
Dyer          Herbert Amesbury 5a 332   
Hibberd     Charlotte Amesbury 5a 332   
SKETCHLEY Ernest Powys Amesbury 5a 332