Shroud for dynamoelectric machine

A ventilation cooling system for a dynamoelectric machine is disclosed, which provides improved cooling efficiency and reduction in windage loss. A first stream of cooling gas is directed into the spider of the machine and transversely through ventilation ducts in the rotor, across the gap, then through corresponding ducts in the stator. A further stream of cooling gas is drawn in between the spider and a shroud which extends inwardly transversely from the stator. This further stream is directed downwardly between the poles of the rotor and then transversely through the gap and stator in conjunction with the first stream.