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Keywords from Image Description:
Biologische Untersuchungen TAF. XV . GUSTAF RETZUS Zur Kenntnis der Spermien der Echinodermen Biol Unters Band XV AF XV Parechinus Parechmus microtub miliaris fc Echinus esculentus Sphaerechinus Paracentrolus Strongylocentrotus Echinocyamus granul lividus droebach pusillus Bryssopsis Mesothuna lyriTera intestin '