NYCTIPITHECUS.—CHRYSOTHRIX. 15 
sibility of a mistake having been made in the origin assigned by Dr. van Patten to 
his example, as the localities given to the specimens obtained by this collector in 
other branches of zoology have not always been free from doubt. 
The habits of this species seem to be very similar to those of W. trivirgatus, as 
described by Humboldt. M. Goudot, who collected Geoffroy’s types, tells us that the 
Mico-dormilons live in small parties or families, which remain concealed in the tops of 
trees during the day, often hidden in heaps of sticks and dead leaves, which are 
perhaps collected by themselves. At nightfall they come forth to feed, but seldom 
seem to wander far, returning regularly to the same places, especially in search of the 
fruit of the guava. During the darkness they continually utter a low cry, which may 
be well rendered by the word dowroucou, dully and feebly pronounced ®, 
2. Nyctipithecus rufipes. 
Nyctipithecus rufipes, Sclater, P. Z.S. 1872, p. 3, t. i. (descr. orig.)’. 
Nyctipithecus vociferans, var.?, Schlegel, Mus. Pays-Bas, vii. p. 214’. 
Hab. Nicaragua, San Juan del Norte (Mus. Brit.)}. 
The still unique type of the Red-footed Douroucouli was received alive from San 
Juan del Norte by the Zoological Society in June 1871; but it soon died; and its skin 
and skull are now in the British Museum. Professor Schlegel has referred to it as 
being possibly a variety of the last species; but, as Mr. Sclater observed in his original 
description, its affinities seem rather to be with the more southern forms, as J. 
_ trivirgatus, Humb., and N. felinus; Spix (=N. azare, Humb.). It agrees with these, 
and differs from NV. vociferans, in its comparatively slender tail, short fur, and well- 
developed ears; whether the nakedness of the latter will prove to be an individual 
peculiarity caused by sickness or not remains to be seen. In the narrowness and 
indistinctness of the facial markings, the absence of a dorsal streak, and the bright 
rufous colour of its hands and feet, it appears to be quite distinct from all its 
congeners. 
5. CHRYSOTHRIX. 
Chrysothriz, Kaup, Thierreich, i. p. 51 (1835). 
Saimiri, Is. Geoffroy, Résumé d. Leg. de Mammalogie, p. 9 (post 1835) *. 
Saimiris, Is. Geoffroy, Compt. Rend. Ac. Paris, xvi. p. 1151 (1843). 
* Saimiri, which has been adopted by some authors, was not used as a generic term by Cuvier in the second 
edition of the ‘ Régne Animal’ (1829), nor by Voigt in his translation of the same (1831), though both have 
been credited with it. It was first systematically employed by Geoffroy as quoted above. I have not been 
able to consult the ‘Résumé’ (published by M. Gervais); but, as the lectures were delivered in 1835, the 
name is at best only contemporary with Kaup’s better known and more elegant title (cf. Geoffroy, Zool. Voy. 
‘ Vénus,’ i. pp. 43-45). 
