Anne
Townland definition:
“The Townland is the smallest administrative unit of land and varies in size. County Roscommon townlands vary in size from two acres (Ballyclare Island) to 2469 acres (Cloonown townland. The average size is 350 acres. It is still the basic address used by rural Irish people for mail and telephone. Each Civil Parish is composed of a number of townlands. A town or village might comprise parts of a number of different townlands. Townlands can come in almost any shape, any size, and with all manner of names (eg. Gaelic, Norman, English, topographical). Note that many townlands in Co Roscommon share the same name. In Australia today we would refer to them as a "sub-division" or "an estate" that had been broken up into varying sized "lots" or "allotments" of land.”
Look at the townland index at
www.leitrim-roscommon.com for more details on each townland
To view the location of townlands in Kilkeevan Civil parish visit
http://www.leitrim-roscommon.com/MAPS/kilkeevin.html
You should check birth/marriage records in adjoining parishes.
At Griffith’s Valuation of Kilkeevan the following persond were called Mallachi:
Mullen Malachy, Cloonchambers townland.
Mahon Malachy, Cloonfad townland.
Of the 34,661 given names recorded for County Roscommon at Griffith’s Valuation, 87 were Mallachi.
Advice from Dr. James Small:
“An Irish research plan is directly dependent on the amount and specificity of the information available. Every effort should be expended toward identifying the exact location, i.e. the name of the townland or parish of the immigrant ancestor. In order to accomplish this goal, one must first search the “New Country (US, Canadian, UK or Australian) sources”. These include a study of all the personal or family, civil, ecclesiastical, LDS (FHL), and other library data available, with an emphasis on localising the family's place of origin in Ireland. Only after exhaustive work in the foregoing areas should the Irish sources be consulted. (Source: Dr. James Small, noted New York genealogist. 1988).”
My advice:
“Do your research in Ireland last.
There does not appear to be a government Department of Fair Trading in Ireland. Usually you “pay your money up front, take your chance and wait ... and wait".
My argument is not about having to pay hefty fees for the information, but about not being able to verify its accuracy.
Ed is an expert in using the IGI (
www.familysearch.org).
I suggest you visit a major public library or your local LDS Family History Centre and use their copy of the LDS British Isles Vital Records Index CDs (set of 16 CDs) and record/order the film numbers of the Broderick records. The microfilms are copies of the actual records. Irish Civil births show the birth townland and occupation of father.
A recent book on Irish research is
Tracing your Irish ancestors, John Grenham, 2006, ISBN 0 – 8063 – 1768 X.
It should be available in most Public Libraries.
John
The Eneclann statement (of nothing!) cost $66.00(Aust) and you two have provided so much more for free. I have sent off to GRO for the marriage cert of my grandparents and fingers crossed, that will provide another clue to work out if any of the Broderick's that you have found are my rellies. The address for the Parish priest is also another useful avenue that I shall pursue. 
There appear to be strong possibilities.