_Smilisca sila_ and _S. sordida_ differ noticeably from other species in the genus by breeding exclusively in streams, where males usually call from rocks or gravel bars in or at the edges of streams (Pl. 9, Fig. 2); sometimes individuals perch on bushes overhanging streams. In the streams, or parts of streams, utilized by these frogs the water is clear, shallow, and has a slow gradient; occasional males have been found calling along cascading mountain streams. Breeding choruses composed of ten or more species of frogs are not uncommon in Middle America, but _Smilisca_ usually breeds alone or with one or two other species and at the most five others. This tendency towards solitary breeding possibly is the result of selection of breeding sites that are unsuitable to many other species of frogs. Nevertheless, many other species of frogs have been found at the breeding sites with the various species of _Smilisca_; these breeding associates (Table 7) are most numerous for _S. baudini_, which has a broad geographic range, including a variety of habitats. _Breeding Behavior_ _Calling sites._--All species of _Smilisca_ usually call from the ground, including rocks and gravel bars; some individuals sit in shallow water near the edge of the pool or stream. Sometimes males of _S. baudini_, _sila_, and _sordida_ call from low bushes or trees near the breeding site. One _S. baudini_ was observed calling while it was floating on the surface of a pond. _Smilisca cyanosticta_, _phaeota_, and _puma_ call from secluded places at the edge of the water or in the water, whereas _S. baudini_, _sila_ and _sordida_ call from open situations. Table 7.--Breeding Associates of the Various Species of Smilisca.