The following page from Biologia Centrali Americana, Insecta Lepidoptera-Heterocera v. 4 shows an interesting example of a proximity search we’d like to support with BHL Name Services – “find species x within n characters/words of species y.”

http://www.biodiversitylibrary.org/page/593637

Halfway through the entry for Lineodes integra you’ll see a character that looks like a crosshair, followed by “Solanum spp. ^4-5,8, S. radula^4-5, S. jasminifolium^4-5, S. tuberosum (=Potato)⁸.” According to Wolfram Mey, the leading lepidopterist of the Museum of Natural History (MfN), Berlin:

The symbol means that the species has been reared from/on the particular plant. The symbol has been in use particularly by the old British authors, particularly Lord Walsingham, and is also used on the labels attached to the specimens. (translation by Dr. Michael Ohl)

What this tells us is Lineodes integra (Eggplant Leafroller Moth) is reared on a variety of Solanum species, including Solanum tuberosum (Potato). This example was uncovered during a Name search for Solanum tuberosum; the resulting bibliography included a link to this volume on insects from the Biologia Centrali-Americana, which seemed unusual given the search was for a plant species. This demonstrates why we’d want to facilitate proximity searches, so that users could find pages where both Lineodes integra and Solanum tuberosum occurred to aid in the discovery of predator-prey, plant-pollinator, or other coevolutionary relationships.

This example also suggests that our OCR algorithms are woefully inadequate to infer these kinds of relationships through automated means; the crosshair symbol was identified as ©.