We have seen no specimens from Nicaragua that are identifiable as _Molossus bondae_, another relatively small species that has been reported from Greytown (Miller, 1913a:89) and from elsewhere in Central America by other authors (Goodwin, 1942c:145; Handley, 1966b:772; Gardner _et al._, 1970:727). Our examination of the female holotype of _M. bondae_ reveals that it is larger than _M. molossus_, corresponding in size to females recently reported from Costa Rica by Gardner _et al._ (_loc. cit._), and that _bondae_ has dark-based hairs. The two males reported by Goodwin (_loc. cit._) from Honduras as _bondae_, would seem to be too small for that species, based on the measurements listed; also, these specimens allegedly have white-based hairs and probably represent _M. molossus_ as here defined. Molossus pretiosus pretiosus Miller, 1902 _Specimens._--_Boaco_: Los Cocos, 14 km S Boaco, 220 m, 28; San Francisco, 19 km S, 2 km E Boaco, 200 m, 3. _Carazo_: 3 km N, 4 km W Diriamba, 600 m, 25. _Managua_: 6 mi WSW Managua, 3. This relatively large mastiff bat has not been reported previously from Nicaragua. Specimens from several localities in Boaco were captured in mist nets over streams; most of those from northwest of Diriamba were shot in the early evening as they foraged high around large trees in a coffee finca, but several were netted over a water-filled concrete tank or found in the water in the tank as detailed in the account of _Eptesicus furinalis_. At Los Cocos, bats that we netted seemed to be emerging from a hollow located high in a tree over the stream. Selected measurements of _M. p. pretiosus_ from Nicaragua, which compare favorably with those of topotypes from Venezuela, are listed in Table 4 along with measurements of _M. ater_ and _M. sinaloae_. The taxonomic relationships of _M. pretiosus_ and _M. ater_ are less than clear, and some authors (Handley, 1966b:773, for instance) have suggested that the two may be conspecific. Whatever their ultimate relationships may prove to be, two distinctive taxa seem to be present in Nicaragua; the larger is assignable to _ater_ and the smaller to _pretiosus_, as currently understood. Furthermore, the presumed presence of two large _Molossus_ with dark-based hairs elsewhere in Central America (Dilford C. Carter, personal communication) and in southeastern México (Goodwin, 1956:4; Goodwin and Greenhall, 1964:20) argues for specific recognition of _pretiosus_.