Matschie (Sitzungsberichte der Gesellschaft Naturforschender Freunde zu Berlin, Jahrgang 1917, p. 284 (for April), September, 1917) applied the name _Micoureus canus_ to a specimen on which the locality was no more precise than Nicaragua. Comparison of Matschie's description with specimens in the United States National Museum (including the holotype of _Philander centralis_ Hollister and referred specimens of _Philander laniger pallidus_ Thomas) reveals that Matschie's specimen was intermediate in coloration between the other two kinds of woolly opossums named above and that there is nothing distinctive, in the specific sense, in the cranial measurements which Matschie published (_op. cit._). _M. canus_, therefore, may be merely an intergrade between the two previously named woolly opossums (_C. d. centralis_ and _C. d. pallidus_), an individual variant of a previously named kind, say, _C. d. pallidus_, or a valid subspecies. If it is a recognizable subspecies, it probably comes from somewhere in the eastern half of Nicaragua. As a means of handling the name, _Micoureus canus_ Matschie, we tentatively place it as a subspecies of the species _Caluromys derbianus_. The name may, therefore, stand as _Caluromys derbianus canus_ (Matschie), with type locality in Guatemala. ~Caluromys derbianus fervidus~ (Thomas) Elliott (Field Columb. Mus. Nat. Hist., Publ. No. 115, Zool. Ser., 8:5, 1907) lists as _Caluromys laniger pallidus_ a specimen from Honduras that was acquired for the Field Columbian Museum (= Chicago Natural History Museum) by purchase from Ward's Natural Science Establishment of Rochester, New York. On August 4, 1951, in the Chicago Natural History Museum, we found in the catalogue of the collection of Recent mammals an entry for a male _Caluromys_ bearing catalogue number 6 and listed as from "San Pedro Sula [Honduras]. From Wards. Mounted". In the collection of study specimens there is no specimen from Honduras that was purchased from Ward's, mounted or unmounted. In the sealed, glass-fronted, exhibit cases of mammals on display there is one, and only one, _Caluromys_. It is presumed to be specimen No. 6. This specimen is not _C. d. pallidus_ because it is too dark. It could be _Caluromys derbianus fervidus_ and we tentatively refer it to that subspecies. ~Caluromys derbianus pallidus~ (Thomas) From Puntarenas, Costa Rica, Harris (Occas. Papers Mus. Zool. Univ. Michigan, 476:7, October 8, 1943) listed as _Caluromys laniger centralis_ a female, skull and skin, No. 62702 in the Museum of Zoology of the University of Michigan. We have examined this specimen, the color of which is darker than in some other specimens of _C. d. pallidus_ but lighter than that of specimens of _C. d. centralis_ (for example, specimens from Turrialba, Costa Rica) and on basis of color we refer No. 62702 to _Caluromys derbianus pallidus_. ~Scalopus aquaticus aereus~ (Bangs)