there was a brilliant Pleiades of neurologists in Frankfurt

Example of the use of metaphors in a scientist's writing:

"…many practicing physicians…have succeeded in organising private laboratories and have brought honour to themselves and their countries through valuable biological discoveries. From among thousands, let us mention Virchow, who wrote his celebrated work on cellular pathology while a physician in Frankfurt; Robert Koch, a practicing physician in Potsdam, whose research breathed new life into bacteriology through fruitful technical advances and excellent observations; and the brilliant Pleiades of neurologists in Frankfurt (not a university city), where men such as Weigert, Ehrlich, and Edinger devised valuable research methods for histology."

Santiago Ramón y Cajal (1999). Advice for a Young Investigator. The MIT Press. (Translation of 4th Spanish Edition, 1916)

[There could be a collective noun here – a 'Pleiades of neurologists'?]