Dog cardiac muscle longitudinal section (l.s.) is the 9th slide in the Amscope 50PC prepared slides. A cardiac muscle is found only in heart. These muscles are involuntary i.e. they contract and expand automatically to keep heart pumping. I am not 100% sure but most likely the cark blue dots in the micrographs are the nuclei.
Micrographs [19 July 2015]
Amscope 50PC Prepared Slides
This post lists all the micrographs I have done from the Amscope 50PC prepared slides.