Image: Hemocyanin Example

Description: Underside of a Cancer productus crab. If you every doubt that arthropods have pigment in their blood which have an open circulatory systems (blood runs free in the body without vessels), turn over a crab and if you are a little lucky, you will see the purple stain seen here left from the pigment. They do not have hemoglobin, but sure do have hemocyanin.
Title: Hemocyanin Example
Credit: originally posted to Flickr as Hemocyanin Example
Author: Jerry Kirkhart
Permission: This image, which was originally posted to Flickr.com, was uploaded to Commons using Flickr upload bot on 19:06, 14 July 2010 (UTC) by Howcheng (talk). On that date, it was available under the license indicated. This file is licensed under the Creative Commons Attribution 2.0 Generic license. You are free: to share – to copy, distribute and transmit the work to remix – to adapt the work Under the following conditions: attribution – You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). http://creativecommons.org/licenses/by/2.0 CC BY 2.0 Creative Commons Attribution 2.0 truetrue
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