SCIUEIDJ3— SCIURDS BOOTIILE. 743 



along the sides, midway between the edge of the ventral surface and the 

 middle of the back, and in having rather less white below. In No. 11412, 

 the color of the middle of the back is nearly uniform blackish-brown, with a 

 quite well-marked grayish subdorsal band ; the ear-patches are pure white, 

 and there are large areas of white on the ventral surface. In No. 11411, the 

 upper parts are dull faded reddish-brown instead of blackish-brown ; the light 

 lateral band is still better marked, and the white below is restricted to a spot 

 at each arm-pit. Four other specimens are similar to the last, except that 

 the lateral band is more or less whitish, and the tail is more broadly edged 

 with white. Tlie white of the lower surface is sometimes confined wholly to 

 tlie throat and breast, and sometimes forms a narrow, more or less interrupted, 

 mesial line, widening over the posterior part of the ventral surface. In No. 

 11421, the lower surface is rusty-yellow, with the upper parts paler than in 

 any of the preceding. No. 8506 (from Nicaragua) is wholly pale yellowish- 

 brown above and rusty-yellow below, with white arm-pits. The above- 

 mentioned pale-grayish lateral band is placed high up on the sides, and' does 

 not correspond in position with the usual "lateral line" which marks the 

 division of the ventral from the dorsal surface. 



As would be expected, these phases of coloration have given rise to 

 numerous synonyms. Lesson's Macroxus adolphei and M. pyladei seem bolli 

 referable here, the former agreeing with No. 11364, described above, except 

 that the entire lower parts are white instead of having the white restricted to 

 irregular large patches; the latter (M. pyladei,) agrees closely with (he usual 

 Costa Rican phase of this species, in which the ear-patches and the whole 

 lower surface are rufous.* Both were described from Central American 



* Lesson's above*cited work beiDg rare in Araericau libraries, I append an exact transcript of his 

 descriptions, kindly furnished me by Dr. E. J. Nol:\n, Secretary of the Academy of Natural Sciences of 

 Philadelphia, from the copy of Lesson's work contained in the Academy's library, the only copy in this 

 country of which I have knowledge: — 



" 19. L'Ecureuil d'Adoithe. 



" (Macroxus Adolphei, Lesson) 



"Cet ccurouil, par son faeies, rappelle l'eeureoil du Fi/lade, et cepetidant sa coloration estdiffe'rente. 

 Le male et la femelle ont etc' tuCs par mou l'rere, Adolphe Lesson, dans les forets qni avoisineut Realcjo, 

 dans la province de Nicaragua, du centre-Ame'iique. Est-ce une varied du suivant? 



"Plus fort que lo pylade, l'eeureuii d'Adolphe a la queue de la longueur du corps, et cette partic a 

 la mcnie nature de poils et la nteme coloration que le pylade, excepts son sommet, qui a une touffe noire 

 et un bouquet blanc terminal. Les poils de cette queue sont roux endessus, ond.es denoiret termiues de 

 blanc. Lo blanc est plus apparent sur les portions laterales et en dessous. 



" Le male a le dessus de la (etc brun tiquet6 de gris, le dessus du corps vari<5 de noir luisant et de 

 roux vif par ondulatious; le dessus des membres est egalement varie' de roux et de brun; niais les ex- 

 trciuites en dessus sont brnues tiquetees de gris-rojix. Deux grosses touflcs blanc-neigenx, placees der- 

 liere les oreilles, trancheut sur le pelage, et le pylade a deux plaques de nieine forme, rouge chamois • 



