1853.] 405 



elusions may not in any instance prove erroneous. I do not think that the short 

 and defective descriptions of others have misled me ; although such might well 

 have been the case. The following descriptions are made as full as possible, 

 for the time has past when short descriptions of half a dozen words can be of any 

 use ; the unusual number of objects claiming our attention at the present day in 

 the three kingdoms of nature, require them to be so drawn up that they never 

 can be too minute, nor their details too extended. 



The most inconceivable confusion has been introduced into Natural History 

 by the publication, a few years ago, of a Fauna of the United States. An author 

 who was scarcely capable of forming a scientific idea, introduced himself into a 

 place, which a more modest man would have hesitated to occupy, and by as- 

 suming discoveries to which he had no right, and imposing names of his own 

 upon animals which had long been known under other names, has dishonestly 

 attempted to rob the real discoverers of the credit to which they were entitled. 



Thus, the rubbish of synonomy has been increased, and doubt and uncertainty 

 introduced where all might have been plain and distinct. I beg leave to offer 

 a few instances of this author's conduct in this place ; others will be produced 

 hereafter. Harlsn, in his Fauna Americana, states that the Arvicola amphibius 

 of Europe is common in this country. Now, there is no proof that he ever saw 

 this animal living or dead. He gives a description which is translated verbatim 

 from Demarest, and shows a woful ignorance of the French langyage by trans- 

 lating '"' plus clair " clearer, instead of paler. Again, he tells us that the Mus 

 sylvaticus is a native of the United States ; and here again he makes free with 

 the Frenchman's words, and again mistranslates. This animal was never seen 

 living on this side of the Atlantic. 



In the following descriptions I have admitted nothing which could be con- 

 sidered common to all the species of any genus, such as the color of the teeth, 

 the hairiness of the posterior inner angle of the mouth, the squamosity of the 

 under side of the toes, or the color of the eyes ; all those matters merely fill up 

 space, and ought from the first to be known as unvarying generic, not specific 

 characteristics. Comparisons with other species mixed with the genuine cha- 

 racters, " notae collatitiae," so much reprobated by Linnaeus, have likewise been 

 studiously avoided. 



1. Arvicola. apella. Auribus brevissimis, sub pilis occultis, intus et extus 

 pilosis. Pedibus gracilibus, brevibus. Cauda brevi, supra obscure badia, subtus 

 cinereo-plumbea. 



Hah. In Pennsylvania in agris cultis. (Dr. Woodhouse.) 



Hair dark lead color, above tipt with brown, redder on the sides ; beneath 

 with gray, inclining to brownish on the chin and throat. Head short, blunt ; 

 ears very short, rounded, slightly hairy both within and without, entirely con- 

 cealed under the fur, antitragus short, semicircular. Legs very short ; feet pale 

 brownish, covered with short, shining hair ; thumb tubercle, furnished with a 

 short blunt nail. Tail very short, above brown, beneath grayish. Length, in- 

 cluding the tail, in. 4'7 ; head l* ; ears -2 ; foreleg -5 ; hind leg 1-1 ; tail ?. 



2. Arvicola edax. Brevis et robustus, supra spadiceo et nigro permixtus. 

 Auribus extra pilos exstantibus. Cauda mediocri, supra nigra, subtus cinerea. 



Hab, In California. 



Body short and thick. Hair plumbeous black, above and on the sides tipt 

 with shining brown mixed with black, beneath tipt with grey. Head short, 

 blunt, ears round, not entirely concealed under the fur, hairy within and without, 

 antitragus large, semicircular. Feet covered with short, shining gray hair, 

 thumb, tubercle, with a short, very blunt nail. Tail moderate, hairy, above, 

 dusky beneath, grey, with a slight tinge of brownish 



Length as before, in. ^^^ ; head 1-4 ; ears -5 ; foreleg 1*3 ; hind leg 1'5 ; tail 1.5. 



3. Arvicola austerls. Supra fusco et nigro permixtus, subtus obscure 

 schlstos7is. Auribus extra pilos exstantibus, extus pilosis. Cauda gracili, dense 

 pilosa. 



Hab. In Wisconsin. (Prof. Baird ) 



