Embryogenesis and development (image) NIH/National Human Genome Research Institute Share Print E-Mail Caption Timing of germ cell formation in Hydractinia versus most animals. Credit Timothy DuBuc, Ph.D. Swarthmore College Usage Restrictions Please provide credit to the artist and institution when using the image. This image may only be used with reports of this research. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.