:' ^ -rt 





78 



MONOOUA1MI8 OF NORTH AMERICAN KODENTIA. 



L 1 



470!), lire not marked lor locality, hut proljultly came from Ohio, Wisconsin, 

 or iMiihigaii, and are really his types. They arc exactly the size of ordinary 

 ieucopus; tiio tail a little shorter, relatively, tliali the average of leucopus, but 

 not shorter than is often found in Ieucopus; and they an; colored exactly as 

 in gossi/piiius, the u|)|»er parts being very dark, the under impure white, and 

 the tail indistinctly bicuKir. 



Here, then, is an exactly intermediate form between Ieucopus ami gossy- 

 pinus, proving that the latter cannot properly be regarded as specifically 

 tlitlerent from the former. 



It is ol>viousIy a matter of indilTerence where we make our break in the 

 chain between the two ; /. c, whether we assign the links "cognatus" to one or 

 the other. Practically, however, it will be found most convenient to assign 

 "cognatus LeC." to Ieucopus, so that we only recognize the extreme of differ- 

 entiation in gossi/piiius. Tiiis course is the more commendable, since "cog- 

 natus Baird", based as above explained, is assuredly Ieucopus. 



Taiii.k will.— j:,i«l of ijifdmeiu of Hespkromys i.rucopuh riir. uossypinl's. 



' We licHitate In tlie determination of this speoiuien, since part of its size is due to overstuffing; 

 the under parts are white, and the tail sharply bicolor; the locality, too, is against the sup|HMition that 

 it is goftj/pinm ; and it h accompanie<l by other Kansas s|iecimenB that we cannot determine, and acme 

 that are certainly purr liucopm. In the length of the feet, however, and in Keneral coloration, it seeiua 

 to agro« better wit!- _-i)ii!ipmii» than with true leucoput. Dr. Ocsner's specimens, likewise, we refer here 

 on account of lorp'.ity and their large size, though the month, feet, and tail underneath, are very pnre 

 white, and the under parts nearly su. (These specimens are both males, and exhibit the maximum 

 development of the testes we have over seen in the species. The glands form an immense bulging man 

 on the nates, about } long by } wide, of flattened, obUmg shape, quite sharp-pointed behind, and mostly 

 divided by a deep median raph£.] 



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