Geographically, pullus is partly isolated by the Cerros De Villaguaire and the Cerros El Zapotillo to the west and the Cerros De Azaculapa to the north. Certain individuals of a series of specimens, referable to B. m. nigrescens, from 1 mi. NW San Salvador and 1 mi. S Los Planes, El Salvador, are intermediate in coloration between that subspecies and pullus. Three of 28 specimens from El Salvador possess the mid-ventral white stripe.
Table 2.—Cranial Measurements (in millimeters) of Adults of Four Subspecies of Baiomys Musculus
Table headings:
- Col A: Occipitonasal length
- Col B: Zygomatic breadth
- Col C: Postpalatal length
- Col D: Least interorbital breadth
- Col E: Length of incisive foramena
- Col F: Length of rostrum
- Col G: Breadth of braincase
- Col H: Depth of cranium
| A | B | C | D | E | F | G | H | |
| Baiomys musculus handleyi, | ||||||||
|---|---|---|---|---|---|---|---|---|
| Sacapulas, El Quiché, Guatemala | ||||||||
| Number of specimens | 8 | 8 | 8 | 9 | 9 | 9 | 8 | 8 |
| Type 275604 ♀ USNM | 20.0 | 10.4 | 7.3 | 4.0 | 4.5 | 7.3 | 9.7 | 7.1 |
| Average | 19.6 | 10.5 | 6.9 | 4.0 | 4.2 | 7.2 | 9.8 | 7.1 |
| Maximum | 20.7 | 11.0 | 7.4 | 4.0 | 4.5 | 7.7 | 10.2 | 7.2 |
| Minimum | 18.8 | 10.2 | 6.4 | 3.9 | 4.0 | 7.0 | 9.7 | 6.8 |
| Baiomys musculus pullus, | ||||||||
| 8 mi. S Condega, Esteli, Nicaragua | ||||||||
| Number of specimens | 17 | 17 | 15 | 17 | 17 | 17 | 17 | 17 |
| Type 275605 ♀ KU | 19.2 | 10.2 | 6.8 | 3.8 | 4.3 | 6.8 | 9.5 | 7.0 |
| Average | 19.3 | 10.2 | 7.0 | 3.9 | 4.3 | 7.0 | 9.6 | 7.0 |
| Maximum | 19.8 | 10.6 | 7.3 | 4.1 | 4.6 | 7.4 | 10.0 | 7.3 |
| Minimum | 18.9 | 9.7 | 6.8 | 3.8 | 4.0 | 6.5 | 9.3 | 6.8 |
| Baiomys musculus grisescens, | ||||||||
| Comayaguela, Guatemala | ||||||||
| Number of specimens | 6 | 7 | 7 | 7 | 7 | 6 | 7 | 7 |
| Average | 19.7 | 10.5 | 6.9 | 3.9 | 4.1 | 7.1 | 9.6 | 6.9 |
| Maximum | 20.3 | 10.9 | 7.2 | 4.1 | 4.4 | 7.3 | 9.9 | 7.1 |
| Minimum | 19.2 | 10.2 | 6.7 | 3.7 | 3.9 | 6.8 | 9.3 | 6.8 |
| Baiomys musculus nigrescens, | ||||||||
| Valley of Comitán, Chiapas, México | ||||||||
| Number of specimens | 14 | 14 | 13 | 14 | 14 | 14 | 14 | 14 |
| Average | 19.5 | 10.1 | 7.1 | 3.8 | 4.4 | 6.9 | 9.3 | 6.9 |
| Maximum | 20.3 | 11.1 | 7.4 | 4.0 | 4.6 | 7.4 | 9.6 | 7.3 |
| Minimum | 19.1 | 9.8 | 6.7 | 3.6 | 4.2 | 6.6 | 9.0 | 6.7 |
Albert Alcorn wrote in his itinerary that some of the type series were taken shortly after lunch (I assume this would mean near noon) near a small creek, and that the specimens from 9 mi. NNW Esteli were trapped in wood piles and rock piles about dusk.