38 BTT.T.F.TIX 1091. 17. S. DEPAETMEXT Or AGEICULTVKE. \ BuS**^. 
Use this poison within live days after mixing or retain in air-tight con- 
tainers. 
Caution. — All poison containers and all utensils nsed in the preparation of 
poison shonld be kept plainly labeled and out of reach of children, irresponsible 
persons, and live stock. 
A spoonful of the poisoned grain scattered about the used entrances of a 
mound is sufficient, and prebaiting is not necessary, as with prairie do^s. 
A word of caution should perhaps be offered in connection with 
control measures. As man has come to occupy a greater portion of 
the earth's surface, and as he has become more and more the master 
of his environment, he has inevitably disturbed the relationships 
of the birds and mammals about him. has upset the balance of 
nature. If he kills the carnivorous species because of their depreda- 
tions on game and live stock he must be prepared to cope with the 
increased hordes of rodents which feed on vegetation and on which 
the carnivorous animals act as a check. If he destroys the rodents, 
he may remove the checks on certain noxious plants or insects. One 
control measure often necessitates the adoption of another. 
This is not to argue against control measures, for if our harmful 
species were not controlled, agriculture in many sections would be 
impossible. Control measures, however, should be scientifically 
founded and applied. The indiscriminate slaughter of supposedly 
harmful species of birds and mammals in the guise of benefiting 
agriculture may do far more harm than good. Many of the species 
which do some harm do far more good. Th£ exact status of each 
suspected species should be carefully determined through an ade- 
quate scientific investigation. If the species is condemned, sound 
control measures should be thoroughly applied. 
In grazing districts or in areas devoted to intensive agriculture the 
death sentence should probably be passed on the banner-tailed kan- 
garoo rat. It should be recalled. ho\rever. that this is the largest 
and one of the handsomest of all its family, and that it is one of 
the most characteristic and interesting of all the desert f aima : where 
extensive grazing or agricultural operations are not undertaken, 
therefore, we feel that the kangaroo rat should be let alone, unless 
its presence threatens infestation of valuable agricultural or grazing 
lands. 
SUMMARY. 
(1) Kangaroo rats may be separated with ease from all other mam- 
mals : the long tail and short and weak fore feet separate them from 
the pocket gophers: the white hip-stripe distinguishes them from 
the pocket mice. The decidedly larger size and the white-tipped tail 
separate Dipodomy* spectabilis spectabUis and D. deserti from D. 
