ITS MONOGRAPHS OF NORTIT AMERICAN RODENTIA. 



species being called Dipus canadensis. The article was immediately copied 

 into Tilloch's Philosophical Magazine,* with reproduction of the colored 

 plates by which it was illustrated. These same figures, representing the ani- 

 mal inactivity and in repose, were also copied by Dr. (i. Shaw in Ins General 

 Zoology in 1801 (plate 1G1), and the species became established upon this 

 name "canadensis", already the third one bestowed upon it. 



The fourth designation of the species, "Dipus americanus", is derived 

 from Barton; it really anticipated Davies's "canadensis", though not in date 

 of publication. In the year 1795, Prof. B. 8. Barton communicated an account 

 of the species to the American Philosophical Society, which body published 

 it in the fourth volume of their Transactions,! bearing date 1799. In this 

 article, the learned and ingenious author named a species, Dipus americanus, 

 on page 115; he discussed at length its probable relationships with Dipus 

 hudsonius of Zimmermann, and with " Mus longipes", coming to the conclu- 

 sion it was distinct; and finished with an interesting account of its habits. 

 Some years later, the same writer presented to the society a second paper J 

 on the species, devoted to further consideration of the creature's habits, 

 with special reference to its torpidity or hibernation. These excellent 

 accounts of Professor Barton's have probably not been excelled in accuracy 

 of detail. 



We thus see how the species came to be generally known by three dif- 

 ferent names, — hudsonius, canadensis, and labradorius, — to say nothing of the 

 "Mus longipes". Later authors are nearly equally divided in their use of 

 these terms, but hudsonius clearly has priority. Coming to later synonyms, 

 I find a quotation of a Gerbillus sijlvaticus, a name said to have been proposed 

 by S. L. Mitchill, without accompanying description; and also of a Meriones 

 nemoralis, attributed to Is. GeoiTroy St. Bilaire. These references I have not 

 been able to verify. 



After treating of "Gerbillus''' canadensis, in his Fauna Americana, in 

 1825, apparently from fair acquaintance with the animal, Dr. R. Harlan, in 

 1839, § described specimens from Philadelphia as a new species under the 



* An Account "I' the Jumping Mouse of Canada, Dipus canadensis. By T. Davies. < Tilloeh's Phil. 

 Mag. i, An;;. 1798, pp. 285-287, pi. viii, figs, (colored) 1, 2. (From Tr. Linn. Soc. iv, 1798, pp. 155-157.) 



tSome account <>l an Americau species of Dipus or Jerboa. < Trans. Amer. Philos. Soc. iv, No. 

 \ii. 1'p. 111-124, with pi. not numbered opp. p. 1-24. "Read" 1795; vol. dated 1799. 



[Supplement to the account id' the Dipus americanus, in the IV. Vol. of the Transactions of the 

 Society. See No. XII. < Trans. Amer. Philos. Soc. vi, 1804, pp. 14:;, 144. Read Dec. 1803; vol. dated 1804. 



$ On a Now Species of Meriones. Proc. Zool. Soc. Lond. vii, Jan. 1839, p 1. Subsequent to the 

 collection of the author's papers published bj Lydia R, Bailey, under tin- title ef "Medical and Physical 

 Researches" I 8vo, Philada. 1835), 



