E. HESKE 1980 Journal Cerro Mozotol, Chiapas, Mexico the first. Duke caught 1 Heteromys on each of 3 lines, but one of these was only two traps away from where he caught his first. He pulled the line he had near camp and moved it to this area. David also changed location of his trap lines to a similar-looking area atop a ridge near camp. That makes ~200 traps set. Tonight will be the last night of trapping here, then to a hotel to begin karyotyping. Re: animals skinned, tissue samples, etc.— all pertinent data (such as repro. condition) is recorded in D.S. Roger's catalogue to simplify keeping track of data on this series of animals. Turned in ~2100. Cerro Mozotol to Huixtla, Chiapas, Mexico Arose ~0630. Sunny again, clouds like a snowfield over the valleys between the mountains. My W-of-road line yielded a disappointing single capture: 1 Reithrodonomys. The two Reithrodonomys captured in this ravine were both along ledges with lots of overhanging vegetation (such as ferns) and nearby logs + trees. They are large (look like ~15g or so), very tawny colored with orange venters, and tails much longer than body length that appears to be somewhat prehensile. The Reithros David caught seem to be a different species— they are smaller and similar in general size and appearance to the R. megalotis I'm used to