

208 Department of Conservation of Louisiana 



agree with Hollister and Lantz that breeding habits doubt- 

 less vary with climatic conditions. 



Ernest Thompson Seton, 29 in 1909, gave the period of 

 gestation of the muskrat, in the north, Manitoba, for ex- 

 ample, at 30 days. In 1927 Professor Jackson, of the Mani- 

 toba Agricultural College, says: "We have as yet no posi- 

 tive record of the one pair breeding three times [in a sea- 

 son], although it is possible with a gestation period of 30 

 days and a first brood in May, a second in July and a third 

 in September." 



On the other hand, as Professor D. E. Lantz 5 " seems to 

 have become the mouthpiece for those who have declared 

 that the period of gestation is only 21 days, it may be well 

 to quote his very words and ascertain how he came to the 

 conclusion that the period of gestation is three weeks. He 

 wrote: "The period of gestation is possibly no longer than 

 twenty-one days, as with the common rat and probably with 

 the field mouse." This indicates he jumped at a conclusion 

 based on researches and first-hand studies of other animals. 



But as Professor Lantz adds to this assumption: "The 

 young are blind and naked when born, but develop rapidly," 

 one may be excused from accepting his statement as to 

 gestation too seriously, for neither the Louisiana nor the 

 Labrador muskrat are born naked. To the contrary, it was 

 found, from handling young just born that they are covered 

 with a fine, silky covering of hair which develops rapidly. 

 The muskrat "mice" are, however, born with their eyes 

 closed and they do not open for a number of days. 



To indicate the difference between the muskrat and the 

 common house rat, it may be in order to quote Mitchell's 

 observation^ 1 that the young of the house rat "which are 

 born naked and blind, are covered with hair on the eighth 

 day and are able to see on the thirteenth day." 



^Seton, E. T., Life Histories of North American Animals, Vol. 1, p. 538- 

 557. 



30 L.antz, D. E., The Muskrat, U. S. Dept. Agr., Farmers' Bulletin No. 396, 

 p. 15. 



^Mitchell, P. C, The Childhood of Animals p. 4647. 



