Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Swartschewskia papyraceaA sponge surface B ectosomal skeleton C cross section of skeleton D rosette spines on strongyles E strongyles. Abbreviations: chs choanosomal skeleton, dm dermal membrane, es ectosomal skeleton, ia inhalant apertures, st spicular tracts. Scale bars: 10 μm (D), 100 μm (E), 500 μm (A, C), 1 mm (B).
