CARNIVORA 



79 



country, between the native or Maori rat {Mus exulans) and the 

 black rat. For instance BuUer in 1870 in a paper "On the New 

 Zealand Rat," gives figures and descriptions of Mus rattus. 



The black rat became enormously abundant in the early days of 

 settlement, and used to move about the country in vast armies. The 

 settlers, bush fellers and saw-mill hands of fifty to seventy years 

 ago, have recorded how invasions of them in countless swarms used 

 to move through their district, climbing everywhere, and eating every- 

 thing that was of a vegetable nature. Oldfield Thomas, in the article 

 already quoted, says: "All the world over Mm rattus takes to roofs 

 and trees on meeting its formidable rival Mus decumanus, to which 

 it leaves the gutters and cellars^." 



In 1840 Messrs Dodds and Davis of Sydney established a farming 

 settlement at Riccarton, close to where Christchurch now stands, and 



sent down James Heriot (or Hariot), as manager, two farm hands, and two 

 teams of bullocks. They ploughed and cultivated about thirty acres of land 

 and secured their crops. But in less than a year they decided to abandon 

 all further efforts. Numberless rats attacked the garnered stores, and the 

 bar at the mouth of the river or estuary proved a sad obstacle to shipping 

 whatever grain had been spared by the scourge of rats. 



'■ In his presidential address to the Royal Society of New South Wales on ist 

 May, 1918, Dr J. Burton Cleland gives some very interesting information on "the 

 Rats that Travel by Sea." I think his remarks on the subject are worthy of quotation 

 in full. "As the old English black rat (Epimys rattus), including the Alexandrine 

 variety {E. rattus alexandrinus), the Norway rat (Epimys norvegicus {decumanus)), and 

 the common house mouse (Mus musculus), are alt subject to plague, it is of consider- 

 able interest to see which of these species is most prone to travel by sea. The most 

 frequent traveller of the three would naturally be looked on, other factors being 

 equal, as the most Ukely introducer of the plague bacillus into unaffected parts. 

 For the purpose of putting this matter beyond dispute, I have had a list prepared 

 of all the rats and mice submitted for examination to the Microbiological Laboratory 

 under my charge, from vessels berthing in the cosmopolitan port of Sydney between 

 April i5th, 1913, and April 14th, 1917. During the period rats or mice were found 

 in fumigation by the Commonwealth Department of Quarantine on 189 vessels, 

 after the accomplishment of 325 voyages .... The ships belonged to all nationalities, 

 though naturally British vessels much predominated, whilst the voyages they made 

 included coastal, interstate and overseas in all directions. On the 325 voyages made 

 by the 189 vessels, 



Epimys rattus was present in 293 . 



2968 individuals were found and submitted, an average per voyage of 9. 

 Epimys norvegicus was present in 3. 



7 individuals were found, an average of -02 (of these vessels one came 



from Vancouver, and one from Noumea). 



Mus musculus was present in 53. 



487 individuals were found, an average of 1-5. 



The largest numbers of mice were found on vessels trading with the North Coast 

 of New South Wales, and an undue proportion of such vessels yielded mice, 

 probably as a result of the frequent carriage of fodder, mice were only occasionally 

 found on vessels from overseas." 



