The Lesser Antilles, extending some 500 miles from Anguilla on the north to Grenada on the south, form an archipelago connecting the Greater Antilles with Trinidad and the South American mainland.¹) Bats comprise the major segment of the extant mammalian fauna of the Lesser Antillean islands and the distribution and variation of chiropterans in this area long has interested systematists and zoogeographers. A revival of this interest in the past decade has resulted in a number of published contributions — KOOPMAN (1958, 1959, 1968), HUSSON (1960), DE LA TORRE (1966), DE LA TORRE & SCHWARTZ (1966), JONES & SCHWARTZ (1967), SCHWARTZ & JONES (1967). Still, much remains to be learned. Nineteen species of bats are on record from the Lesser Antilles. For purposes of discussion, these can be divided roughly into three groups or zoogeographic components: 1) species that have invaded the southern part of the archipelago relatively recently from South America; 2) species that represent endemic (and presumably fairly old) Antillean genera; and 3) species or species groups that are widely distributed in the Antillean region and elsewhere in the American tropics. It is convenient to discuss the Lesser Antillean fauna under these three groupings, and we have done so beyond.