Hydrozoa, most often living in oceans, commonly occur in two different main forms: a fixed polyp form of very simple body structure (fig. 5-12) and a freely swimming medusa form of higher organization (fig. 1-4). In most Hydrozoa both forms are associated through alternation of generation (Metagenesis); Polyps originate from the fertilized eggs of Medusae; these again develop through budding out of Polyps (fig. 9,11). There are, however, many Polyps that do not build Medusae, and many Medusae, out of whose eggs again Medusae generate (through Hypogenesis, without alteration of generation). The Polyps presented on this plate are characterized by a beautiful red, orange and yellow coloration; they belong to the order of the Tubulariae (fig. 5-12) and are in an alteration of generation with the Anthomedusae (fig. 1-4).
Translation of the original German introduction by Ernst Haeckel:
Phylum of Cnidaria; - class of Hydrozoa; - subclass of Hydroidea; - order of Tubulariae.
Translation by VR Translators Bangalore
This is one of the 100 pop science biology illustrations that were published from 1899 – 1904 in Leipzig by Ernst Haeckel through Verlag des Bibliographischen Instituts.
We've scanned the original lithography at 1200dpi on the Epson A3 scanner of A3 scanner huren. You can download a 400dpi JPEG here.